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DESIGN

GUIDE

Military Family HousingEnergy-Efficient Revitalization and New Construction

July 1996

Prepared for:

United States Air ForceUnited States Department of Energy

Prepared by:

Oak Ridge National LaboratoryNational Association of Home Builders Research Center

Military Family HousingEnergy-Efficient Revitalizationand New Construction

M. P. TernesR. L. WendtJ. O. KolbOak Ridge National Laboratory

S. ScullyNational Association of Home Builders Research Center

July 1996

Prepared for:

United States Air ForceUnited States Department of Energy

Prepared by:

Oak Ridge National LaboratoryOak Ridge, Tennessee 37831Managed byLockheed Martin Energy Research Corp.for theU.S. Department of Energyunder contract DE-AC05-96OR22464

DESIGN

GUIDE

Design Guide for Military Family Housing:Energy-Efficient Revitalization

and New Construction

Air Force Program Management Offices:

Headquarters United States Air ForceOffice of The Civil Engineer

Directorate of HousingDSN 227-0157(703) 697-0157

and

Air Force Civil Engineer Support AgencyCivil Engineer Technical Support

DSN 523-6361(904) 265-6361

Disclaimer

This document was prepared as an account of work sponsored by anagency of the United States Government. Neither the United StatesGovernment nor any agency thereof, nor any of their employees, makesany warranty, express or implied, or assumes any legal liability orresponsibility for the accuracy, completeness, or usefulness of anyinformation, apparatus, product, or process disclosed, or represents thatits use would not infringe privately owned rights. Reference herein toany specific commercial product, process, or service by trade name,trademark, manufacturer, or otherwise, does not necessarily constitute orimply its endorsement, recommendation, or favoring by the UnitedStates Government or any agency thereof. The views and opinions ofauthors expressed herein do not necessarily state or reflect those of theUnited States.

CONTENTS

1. INTRODUCTION1.1 Need for This Guide .................................................................................................................... 1-11.2 Opportunities and Challenges ..................................................................................................... 1-31.3 Use of This Guide........................................................................................................................ 1-41.4 Preparation of Instructions to the Architect/Engineer ................................................................ 1-5

2. RESPONSIBILITIES OF THE ARCHITECT/ENGINEER2.1 Purpose ........................................................................................................................................ 2-12.2 Design, Analysis, and Selection of Options for New Housing .................................................. 2-22.3 Inspection, Analysis, and Selection of Options for Revitalized Housing .................................. 2-42.4 Specification of Energy-Efficiency Options............................................................................... 2-8

3. DESIGN, ANALYSIS, AND SELECTION OF OPTIONS FOR NEW HOUSING3.1 Overview ..................................................................................................................................... 3-13.2 Selection of ECMs Using COSTSAFR ...................................................................................... 3-23.3 Details of the Point System Work Sheet..................................................................................... 3-43.4 Example of Point System Work Sheet........................................................................................ 3-83.5 Design Considerations................................................................................................................. 3-17

4. INSPECTION, ANALYSIS, AND SELECTION OF OPTIONS FOR REVITALIZEDHOUSING4.1 Inspection..................................................................................................................................... 4-1

4.1.1 Energy Use Review........................................................................................................ 4-24.1.2 Inspection Process.......................................................................................................... 4-44.1.3 General Information.......................................................................................................4-54.1.4 Thermal Boundary Identification................................................................................... 4-64.1.5 Insulation........................................................................................................................ 4-84.1.6 Infiltration....................................................................................................................... 4-94.1.7 Windows and Doors....................................................................................................... 4-104.1.8 Heating and Cooling Equipment.................................................................................... 4-114.1.9 Air Distribution System ................................................................................................. 4-134.1.10 Domestic Water Heating System................................................................................... 4-144.1.11 Other Inspections ........................................................................................................... 4-15

4.2 Analysis and Selection ................................................................................................................ 4-164.2.1 General Information.......................................................................................................4-184.2.2 Thermal Boundary ......................................................................................................... 4-194.2.3 Wall Insulation ............................................................................................................... 4-204.2.4 Foundation Insulation .................................................................................................... 4-254.2.5 Ceiling or Attic Insulation ............................................................................................. 4-324.2.6 Infiltration....................................................................................................................... 4-354.2.7 Roofing........................................................................................................................... 4-394.2.8 Windows......................................................................................................................... 4-404.2.9 Doors .............................................................................................................................. 4-444.2.10 Heating and Cooling Equipment Replacement Options................................................ 4-45

iii

4.2.11 Heating and Cooling Equipment Replacement Selection ............................................. 4-474.2.12 Heating and Cooling Equipment Selection ................................................................... 4-524.2.13 Heating and Cooling Equipment Sizing and Location.................................................. 4-554.2.14 Other Heating and Cooling Equipment Retrofits .......................................................... 4-564.2.15 Air Distribution System ................................................................................................. 4-594.2.16 Domestic Water Heating System................................................................................... 4-624.2.17 Exhaust Systems and Appliances .................................................................................. 4-664.2.18 Lighting .......................................................................................................................... 4-684.2.19 Site Improvements ......................................................................................................... 4-714.2.20 Documentation of Analysis Process .............................................................................. 4-72

5. SPECIFICATION OF SELECTED ENERGY-EFFICIENCY OPTIONS5.1 Overview ..................................................................................................................................... 5-15.2 Infiltration Repair Specifications and Construction Tips ........................................................... 5-25.3 Infiltration Performance Testing of Housing Units .................................................................... 5-45.4 Windows and Doors .................................................................................................................... 5-55.5 HVAC Equipment ....................................................................................................................... 5-75.6 Air Distribution System Repair and Construction Specifications.............................................. 5-115.7 Air Distribution System Performance Testing............................................................................ 5-16

Appendix A. ENERGY INSPECTION FORMS FOR MILITARY FAMILYHOUSING UNITS

Appendix B. BLOWER-DOOR INSPECTOR SELECTION GUIDE

Appendix C. SPECIFICATION FOR MEASURING HOUSING UNITINFILTRATION RATE

Appendix D. SPECIFICATION FOR VISUAL INSPECTION OF ENVELOPEAIR LEAKAGE

Appendix E. SPECIFICATION FOR MEASURING DUCT AIR-LEAKAGE RATE

Appendix F. SPECIFICATION FOR INSPECTION OF DUCT AIR LEAKAGE

Appendix G. ENERGY ANALYSIS FORMS FOR REVITALIZED HOUSING UNITS

Appendix H. DESIGN WEATHER DATA FOR INSTALLATIONS IN THEUNITED STATES

iv

FIGURES

4.1 Sample sketch showing how to identify the thermal boundary for a housing unitusing house plans and sections.................................................................................................... 4-7

4.2 Annual space-heating energy savings per square foot of wall area frominstalling R-13 insulation in the stud cavity of an uninsulated wood-framewall .............................................................................................................................................. 4-21

4.3 Annual space-heating energy savings per square foot of wall area from installingR-5 insulation on the exterior of a wood-frame wall with R-13 insulation alreadyinstalled in the stud cavity ........................................................................................................... 4-21

4.4 Annual space-cooling electricity savings per square foot of wall area from installingR-13 insulation in the stud cavity of an uninsulated wood-frame wall ...................................... 4-22

4.5 Annual space-cooling electricity savings per square foot of wall area from installing R-5 insulation on the exterior of a wood-frame wall with R-13 insulation already installed in the stud cavity ........................................................................................................... 4-22

4.6 Annual space-heating energy savings per square foot of wall area from installinginsulation on the exterior or interior of an uninsulated masonry wall........................................ 4-24

4.7 Annual space-cooling electricity savings per square foot of wall area from installinginsulation on the exterior or interior of an uninsulated masonry wall........................................ 4-24

4.8 Annual space-heating energy savings per linear foot of perimeter length frominstalling R-5 insulation on the perimeter of an uninsulated slab foundation............................ 4-26

4.9 Annual space-cooling electricity savings per linear foot of perimeter length frominstalling R-5 insulation on the perimeter of an uninsulated slab foundation............................ 4-26

4.10 Annual space-heating energy savings per square foot of crawl space ceiling areafrom installing insulation on the ceiling of an uninsulated crawl space..................................... 4-28

4.11 Annual space-cooling electricity savings per square foot of crawl space ceiling areafrom installing insulation on the ceiling of an uninsulated crawl space..................................... 4-28

4.12 Annual space-heating energy savings per square foot of basement ceiling area frominstalling insulation on the ceiling of an uninsulated basement ................................................. 4-31

4.13 Annual space-cooling electricity savings per square foot of basement ceiling areafrom installing insulation on the ceiling of an uninsulated basement ........................................ 4-31

4.14 Annual space-heating energy savings per square foot of attic floor area from installing insulation on the floor of an uninsulated attic............................................................. 4-33

4.15 Annual space-cooling electricity savings per square foot of attic floor area frominstalling insulation on the floor of an uninsulated attic............................................................. 4-33

4.16 Potential annual space-heating energy savings from air-leakage mitigation ............................. 4-374.17 Potential annual space-cooling electricity savings from air-leakage mitigation........................ 4-384.18 Guidelines on use of heat pumps................................................................................................. 4-394.19 Annual space-heating energy savings per square foot of window area from

installing higher-efficiency windows compared with a single-glazed window with a metal frame....................................................................................................................... 4-42

4.20 Annual space-cooling electricity savings per square foot of window area frominstalling higher-efficiency windows compared with a single-glazed window with a metal frame....................................................................................................................... 4-42

v

4.21 Annual space-heating energy savings per square foot of window area from installingstorm windows on single-glazed windows with (a) metal frames without a thermalbreak and (b) nonmetallic frames and metal frames with a thermal break ................................ 4-43

4.22 Air Force guidelines on use of air conditioning.......................................................................... 4-464.23 Annual space-heating fuel savings per square foot of living area for high-efficiency

furnaces and boilers (>90% AFUE) compared with minimum-efficiency units(80% AFUE)................................................................................................................................ 4-48

4.24 Annual space-cooling electricity savings per square foot of living area ofhigh-efficiency air conditioners and heat pumps (12 SEER) compared withminimum-efficiency units (10 SEER)......................................................................................... 4-49

4.25 Annual space-heating electricity savings per square foot of living area of high-efficiency heat pumps (7.5 HSPF) compared with minimum-efficiency units(6.8 HSPF) ................................................................................................................................... 4-51

4.26 Annual space-heating fuel savings per square foot of living area from replacingan existing furnace or boiler with an 80% or 92% AFUE unit................................................... 4-53

4.27 Annual space-cooling electricity savings per square foot of living area from replacing an existing air conditioner or heat pump with a higher-efficiency unit(10 or 12 SEER) .......................................................................................................................... 4-53

4.28 Annual space-heating electricity savings per square foot of living area from replacing an existing heat pump with a higher-efficiency unit (6.8 or 7.5 HSPF)..................... 4-54

4.29 Annual space-heating fuel savings from installing an intermittent ignition device fora gas-fired furnace or boiler with a pilot light that remains lit all year ...................................... 4-56

4.30 Annual space-heating fuel savings from installing a thermal vent damper on agas-fired furnace or boiler installed in an intentionally or unintentionally heatedspace ............................................................................................................................................ 4-58

4.31 Annual space-heating fuel savings from installing an electric vent damper on afurnace or boiler installed in an intentionally or unintentionally heated space.......................... 4-58

4.32 Potential percentage energy savings from installing a new air distribution system and modifying or repairing the existing system.......................................................................... 4-60

4.33 Fuel selection for domestic water heating................................................................................... 4-634.34 Annual energy consumption—gas (and oil) hot water system................................................... 4-634.35 Annual energy consumption—electric hot water system ........................................................... 4-644.36 Fuel selection for cooking ranges ............................................................................................... 4-67C.1 Climate correction factor, “C,” for calculating average infiltration rates in

North America ............................................................................................................................. C-2D.1 Wall penetrations under sinks (a) and behind appliances (b) open the interior of the

housing unit to the outside, attic, crawl space, or basement through exterior andinterior walls ................................................................................................................................ D-2

D.2 Attic bypasses connect the interior of the housing unit to the attic but are usually notvisible from within the house...................................................................................................... D-3

F.1 Circumferential joints in ductwork often deteriorate and leak if they lack mechanicalfasteners and were initially unsealed or sealed only with fabric tape ........................................ F-2

F.2 A sheet metal boot in a newly installed duct system is improperly installed, creatinga 1/2-in. gap between the boot and the supply register............................................................... F-3

F.3 A leak to a wall cavity located behind a wall-mounted grill (a). The joints in theductwork behind the grill are also deteriorated and leaking (b) ................................................. F-4

vi

F.4 Use of duct tape rather than mechanical fasteners to secure the connection of a return duct to a junction box at an attic-mounted evaporator allowed the joint to fail, forming a significant return leak.......................................................................................... F-5

F.5 The joint between a return duct and a building cavity used as a return duct was notsealed and mechanically fastened and, following failure, created a large leakage area ............ F-6

F.6 Unfaced interior walls and unsealed penetrations for plumbing and electrical linesin this return plenum allow unconditioned air to be drawn into the return from theattic or the outside ....................................................................................................................... F-6

F.7 An evaporator that is physically too large for and poorly mounted to the furnacecreated a large supply leak .......................................................................................................... F-7

F.8 An unsealed “knockout” for wiring and refrigerator lines and a poorly fitting panelon this attic-mounted evaporator allow attic air to be drawn into the return system................. F-8

vii

TABLES

2.1 Inspection sampling requirements............................................................................................... 2-43.1 Infiltration point work sheet........................................................................................................ 3-53.2 Window shading coefficients ...................................................................................................... 3-64.1 Minimum air changes per hour ................................................................................................... 4-354.2 Maximum air changes ................................................................................................................. 4-364.3 Annual fuel utilization efficiency (%) ........................................................................................ 4-484.4 Air conditioner and heat pump efficiencies ................................................................................ 4-504.5 Characteristics of water heaters .................................................................................................. 4-624.6 Recommended lighting................................................................................................................ 4-705.1 Sealing requirements for duct systems........................................................................................ 5-12H.1 Weather data for U.S. Air Force bases........................................................................................ H-1H.2 Infiltration degree-days for U.S. cities........................................................................................ H-4

ix

ACRONYMS

ACCA Air-Conditioning Contractors of AmericaACH air chanages per hourA/E architect/engineerAFUE annual fuel utilization efficiencyASHRAE American Society of Heating, Refrigerating, and Air-Conditioning Engineers

CAPS Computerized, Automated Point SystemCCT correlated color temperatureCOSTSAFR Conservation Optimization Standard for Savings in Federal ResidencesCRI color rendition index

DHW domestic hot waterDOD Department of DefenseDUERS Defense Utility Energy Reporting System

ECM energy conservation measureEUB energy use budget

gpm gallons per minute

HIR halogen incandescent with an infrared-reflective coatingHSPF heating seasonal performance factorHVAC heating, ventilating, and air conditioning

IID intermittent ignition device

LP liquid petroleumLPW lumens per watt

MBtus millions of Btus

NPV net present value

Pa pascal

SC shading coefficientSEER seasonal energy efficiency ratioSIR savings-to-investment ratioSPP simple payback period

UL Underwriter’s Laboratory

xi

1Chapter

INTRODUCTION

1.1 Need for This Guide ................................................................. 1-11.2 Opportunities and Challenges .................................................. 1-31.3 Use of This Guide..................................................................... 1-41.4 Preparation of Instructions to the Architect/Engineer ............... 1-5

1.1 Need for This Guide

PURPOSE

This design guide has been prepared for useby the architect/engineering (A/E) firmscommissioned by the Air Force to develop thedesign and specification of military familyhousing revitalization and new constructionprojects. It provides the necessary informationand analytical tools for the A/Es to makeprudent and cost-effective decisions regardingthe type and extent of energy conservationmeasures to be provided during the newconstruction or revitalization process. Acompanion retrofit guide has been prepared toidentify and implement energy-efficiencyimprovements in dwellings that are notscheduled for revitalization within the next10 years.

The design guide includes

• step-by-step procedures for analyzing andselecting energy conservation measures innew and revitalized housing;

• detailed diagnostic inspection proceduresthat will identify energy-efficiency problemareas in existing housing; and

• selected specifications for material andequipment installation. The program manager for a revitalization or

new construction project will initiate the use ofthis design guide by (a) specifying adherence tothis design guide in the Request for Proposal orStatement of Work with the A/E (general A/Eresponsibilities are outlined in Chap. 2,“Responsibilities of the Architect/Engineer”),and (b) providing the A/E with energy-relatedinformation as discussed in Sect. 1.4,“Preparation of Instructions to theArchitect/Engineer.”

The A/E will provide the program managerwith documentation of energy analysesperformed and identification of energy-efficiency measures and efficiency levels that

are cost effective for the project (see Sect. 3.2,“Selection of ECMs Using COSTSAFR,” andSect. 4.2.20, “Documentation of AnalysisProcess”). The A/E will also provide theprogram manager with specifications regardingthe installation of recommended efficiencymeasures as outlined in Chap. 5, “Specificationof Selected Energy-Efficiency Options.”

The program manager or designee willreview the energy analyses submitted using acommissioning guide that is a companion to thisdesign guide. The program manager will includein the Request for Proposal or Statement ofWork for construction projects the energy-efficiency measures and efficiency levelsidentified by the A/E as being cost effective, aswell as any installation specifications developedby the A/E.

BACKGROUND

The Air Force family housing revitalizationprogram brings existing dwellings intocompliance with current military constructionstandards, extending their useful life for another20 years. Likewise, new military family housingconstruction continues throughout the Air Forceto meet changing installation needs andmissions. These programs offer uniqueopportunities to economically improve energyefficiency and help meet mandated reductions inenergy consumption. It is important that energyefficiency be thoroughly addressed during newconstruction and revitalization because no othercomparable opportunity will exist for manyyears.

Prescriptive standards have been developedfor new construction and can apply torevitalization, but by themselves they areinsufficient to correct the energy deficiencies ofcurrent Air Force housing and ensure that pastmistakes will not be repeated. Comprehensivediagnostics are needed to identify house-specificenergy-related issues in existing housing, and

INTRODUCTION 1-1

life-cycle cost-effective energy solutions arenecessary to resolve them. The fact thatprevious revitalization efforts have not achievedoptimized energy designs confirms the need forthis guide.

Representative examples of various types ofrevitalized and nonrevitalized housing at thefollowing Air Force bases were inspected duringthe development of the design guide: Shaw AirForce Base, Malmstrom Air Force Base, andAltus Air Force Base. The inspection of eachhousing unit generally included examining thebuilding shell and attic, determining insulationlevels, measuring the air tightness of the unit,and inspecting the space-heating andspace-cooling systems. The purpose of theseinspections was to evaluate the energyperformance of existing housing in order todevelop cost-effective recommendations to beimplemented as part of the new construction andrevitalization process for family housing.

The inspections identified design andconstruction flaws that adversely affect thehousing energy performance and that must becorrected during revitalization and preventedduring new construction. Some recentlyrevitalized units contained many of the sametypes of flaws as the units awaitingrevitalization. These flaws include the following:

• Disconnects and deterioration of the airdistribution duct work and poor system

design cause leakage in the system resultingin a significant increase in energyconsumption.

• Air leaks occur between the conditioned andunconditioned space (primarily to the attic)around unsealed openings.

• Inappropriate design of the air distributionsystem creates unbalanced pressure withinthe conditioned space resulting in increasedinfiltration and exfiltration.

• Poorly defined building thermal boundariesresult in incomplete insulation coverage.

• Insulation is lacking at second-flooroverhangs, under window openings, inbasements, and in crawl spaces.

• Attic insulation depth is highly variedbecause of disruption by maintenancepersonnel working in the attic and windscouring at the eaves.

• Inadequate or blocked attic ventilationresults in potential moisture-relatedproblems.

• Recently installed heating, ventilating, andair conditioning (HVAC) equipment has ahigher efficiency rating than may be costeffective.

• Temperature settings (150ÉF) on waterheaters are excessive.

• No low-flow (2.5 gpm) shower heads havebeen installed.

• Little or no energy-efficient lighting is inuse.

1-2 INTRODUCTION

1.2 Opportunities and Challenges

OPPORTUNITIES

New construction offers the opportunity tobuild housing that provides a comfortable livingenvironment without excessive ongoingexpenditures for energy. Some uniqueopportunities to address energy efficiency arealso available when existing housing undergoesrevitalization. These opportunities include:

• The house is vacant for an extended period.• The scope of the project is large enough to

allow economies of scale (in both designand construction).

• Replacement of whole systems is possible ifneeded.

• Fuel conversion is possible and encouragedwhen economical.

• Energy-efficiency measures can be installedmore easily and less expensively.

CHALLENGES

Several challenges in new construction andrevitalization programs can influence design.These challenges include the following:

• The occupants do not pay for utilitiesconsumed.

• Energy efficiency competes for budgetedfunds with other housing requirements suchas the amount and quality of space provided.

• Local energy managers may have limitedincentive and opportunity to run an effectiveconservation program.

• The actual energy consumption of existinghouses is not accurately known becausehouses lack individual meters. Faultydesign, construction, or operation is notapparent because there is not enoughfeedback to determine when one house typehas an energy problem. Additionally, it isdifficult to measure the payback from anupgrade and verify its benefits.

It is important to note that the comfort ofoccupants drives their conservation actions.Houses with uninsulated slab-on-gradefoundations without carpet are cold. Draftyhouses and houses with uneven heating andcooling are not comfortable, and oversized airconditioning units will not control humidity,causing summer discomfort. Residentscompensate for these discomforts by changingthermostat settings—the primary control theyhave over their environment. Because theseresidents do not pay utility costs (which wouldmoderate their actions), it is especiallyimportant that proper equipment and materialsbe selected for new or revitalized militaryhouses. Marginally effective materials orhigh-maintenance equipment that is prone tobreakdown or inefficient operation should beavoided.

INTRODUCTION 1-3

1.3 Use of This Guide

The organization of this guide follows thenormal process used in developing newconstruction and revitalization projects.

Chapter 2, “Responsibilities of theArchitect/Engineer,” defines what A/Es areexpected to accomplish relative to energyconservation as part of their commission toprepare plans and specifications for Air Forcefamily housing projects (both new constructionand revitalization).

Chapter 3, “Design, Analysis, and Selectionof Options for New Housing,” provides theinformation and methodology needed to selectthe appropriate energy-efficiency optionsneeded to obtain the cost-effective energybudget defined by the ConservationOptimization Standard for Savings in FederalResidences (COSTSAFR) program. The chapterhighlights areas that the A/E is to considerduring the design process and references otherportions of the Guide regarding typicaldeficiencies to be avoided in new constructionand selected specifications needed toaccomplish the work in a satisfactory manner.

Chapter 4, “Inspection, Analysis, andSelection of Options for Revitalized Housing,”

defines the field inspection process to be used indetermining the adequacy of existing energyimpacting conditions. This chapter points outtypical energy-related “problem areas” that havebeen found in many Air Force housing units andprovides the information and methodologyneeded to select among the various energy-efficiency actions available. This chapter doesnot address the inspection of housing relative tothe other criteria and issues related torevitalization.

Chapter 5, “Specification of SelectedEnergy-Efficiency Options,” provides suggestedspecifications to be used to implement selectedenergy-efficiency measures.

The “Inspection, Analysis, and Selection ofOptions for Revitalized Units” and“Specification of Selected Energy-EfficiencyOptions,” chapters of the guide are organized sothat persons from individual design disciplines(architectural, mechanical, and electrical) canaccess information specifically applicable totheir area of expertise. Individual topics arelisted in the table of contents, permitting directaccess to those topics of interest to eachdiscipline.

1-4 INTRODUCTION

1.4 Preparation of Instructions to theArchitect/Engineer

The program manager or initiator of an AirForce family housing construction orrevitalization project is responsible forproviding the A/E with output from theCOSTSAFR and Computerized, AutomatedPoint System (CAPS) programs. This outputdefines the energy budget and design parametersfor each housing type to be addressed in theproject. The COSTSAFR and CAPS programswill be run by the Air Force Civil EngineerSupport Agency (HQAFCESA/CES) at TyndallAir Force Base, Florida, at the request of theMajor Commands.

The program manager will need to providepersonnel at the Civil Engineer Support Agencythe following information for the overall project:

• Proposed occupancy year• Project location• Fuel costs

— Oil ($/gal)— Liquid petroleum (LP) gas ($/gal)— Natural gas ($/therm)— Electricity ($/kWh) The program manager will also need to

provide the following for each unique buildingtype:

• Foundation type

— Slab-on-grade— Crawl space— Basement

• Building type— Single-story ranch— Split-level— Townhouse— Two story

— Apartment— Single-section manufactured— Multisection manufactured

• Planned heating equipment— Furnace (preferred fuel: oil, natural gas,

LP gas)— Heat pump (electric)

• Planned air conditioning?— Yes— No

• Planned domestic hot water fuel— Electric— Gas For new construction, this information

describes acceptable options for housing units.Therefore, more than one foundation type,building type, heating equipment, and domestichot water fuel can be approved. Forrevitalization, because this informationdescribes an existing unit, only one foundationtype and building type can be specified.However, a specific selection for heatingequipment and domestic hot water fuel does notneed to be made.

The instructions provided to the A/E in theRequest for Proposal or Statement of Workshould include the following:

• a copy of the output of the COSTSAFR and

CAPS programs for each unique housingtype,

• a copy of this guide, and• copies of, or references to, all applicable Air

Force codes and standards.

INTRODUCTION 1-5

2Chapter

RESPONSIBILITIES OF THEARCHITECT/ENGINEER

2.1 Purpose .................................................................................... 2-12.2 Design, Analysis, and Selection of Options for New

Housing .................................................................................... 2-22.3 Inspection, Analysis, and Selection of Options for

Revitalized Housing .................................................................. 2-42.4 Specification of Energy-Efficiency Options ............................... 2-8

2.1 Purpose

The purpose of this chapter is to define theA/E’s responsibilities in producing plans andspecifications for new and revitalized Air Forcefamily housing projects that will result incost-effective, energy-efficient dwelling units.The A/E’s responsibilities with regard to thedesign of energy-efficient housing will befulfilled in accordance with this guide throughthe accomplishment of the following tasks:

• design, analysis, selection, anddocumentation of cost-effectiveenergy-efficiency options for new housingunits, or

• inspection, analysis, selection, anddocumentation of cost-effectiveenergy-efficiency options for revitalizationunits, and

• specification of the cost-effectiveenergy-efficiency options identified andbuilding envelope and equipmentperformance verification testingrequirements.

For new construction, energy efficiency willbe partially achieved by complying with variousprescriptive standards referenced in this guide

and the requirements set by the COSTSAFRprogram for each distinct housing type (seeSect. 3.2, “Selection of ECMs UsingCOSTSAFR”). COSTSAFR identifies thecost-effective level of energy efficiency for eachnew housing type at the project’s location. Tofully achieve the intended level of energyefficiency, quality materials and equipment andtheir proper installation must be specified, aswell as verification testing to ensure thateverything is functioning properly (Chap. 5,“Specification of Selected Energy-EfficiencyOptions”).

For revitalization of existing housing, theuse of prescriptive standards is less appropriatebecause existing conditions and deficiencies canlimit the cost-effective application of efficiencymeasures. This guide provides a methodology(see Chap. 4, “Inspection, Analysis, andSelection of Options for Revitalized Housing”)for making cost-effective energy-efficiencydecisions in an environment when such limitsmust be taken into account. As with newconstruction, the specification of materials andequipment, commissioning, and verificationtesting is required.

RESPONSIBILITIES OF THE ARCHITECT/ENGINEER 2-1

2.2 Design, Analysis, and Selection of Options forNew Housing

Chapter 3, “Design, Analysis, and Selectionof Options for New Housing,” will assist theA/E in selecting the appropriate types and levelsof energy-efficiency options for new housingunits. The design process must avoidreproducing flaws typically found in existinghousing as described in Sect. 1.1, “Need forThis Guide,” and throughout Sect. 4.2,“Analysis and Selection.”

AREAS TO BE ANALYZED

The following elements impact the energyefficiency of Air Force family housing and shallbe addressed by the A/E in the analysis phase ofthe design process:

Building Envelope

The entire envelope will be analyzed,thermal boundaries will be defined, andinsulation levels for the entire boundary will bedetermined and specified for the specific climateand fuel cost. Air-leakage locations andbypasses in the building thermal envelope thatallow conditioned air to move directly out of thehouse will be avoided or sealed. Appropriatequality, energy-efficient windows and doors willbe specified.

Heating and Cooling System

The proper heating and cooling equipmentwill be determined for the climate, fuel type andcost, and house load. A life-cycle cost approachwill be used to select the appropriate level ofefficiency. Equipment must be properly sized.Insulation levels for ducts located outside thethermal boundary (in attics, crawl spaces, orunheated basements) must be determined andspecified.

Domestic Water Heating System

The life-cycle cost impact of alternativefuels (electric and natural gas) will be evaluatedand the least costly selected. The efficiencydifference among available equipment will beevaluated on a life-cycle cost basis. Waterconservation opportunities will be identified andincluded in the project to the extent that they arecost effective.

Major Appliances

The life-cycle cost impact of alternativefuels (electric and natural gas) will be evaluatedand the least costly selected. The efficiencydifference among appliances will be evaluatedon a life-cycle cost basis and the one with theleast life-cycle cost selected.

Lighting

The lighting system will be based on acost-effective energy-efficient lighting design.

Site Improvements

Site improvements (landscape andpavement) will be evaluated as to their potentialimpact on the energy performance of thedwelling units. Designs that minimize energyconsumption will be used whenever costeffective.

DOCUMENTATION OF ANALYSIS

A summary of the analysis process shall beaccomplished for each housing type in theproject and be submitted to the programmanager for review and approval. Instructionsfor completing specific forms for this purposeare included in Chap. 3, “Design, Analysis, andSelection of Options for New Housing.”

2-2 RESPONSIBILITIES OF THE ARCHITECT/ENGINEER

STANDARDS FOR NEW WORK

The following manuals are the Air Forcestandards that govern design of new familyhousing: Air Force Instruction 32-6002 datedMay 12, 1994, and Air Force Family HousingGuide for Planning, Programming, Design, andConstruction dated December 1995. Theprescriptive standards and criteria that are listedin these manuals are applicable to constructionof all new buildings.

RESOLUTION OF CONFLICTINGCRITERIA

Conflicting criteria will be resolved in thefollowing order: (a) adhering to the project’sStatement of Work, (b) adhering to theappropriate Air Force standards manualspreviously cited, and (c) selecting the criteriathat are shown to be most cost effective asapplied to the specifics of the project.


2.3 Inspection, Analysis, and Selection of Options forRevitalized Housing

In conjunction with the detailed houseinspection required by other parts of the A/E’scontract, inspectors shall investigate existingconditions that have the potential tosignificantly impact the energy consumption ofthe units being revitalized.

Before inspections begin, current energyconsumption data will be examined to determinethe current performance and the extent ofexisting problems. A methodology of assessingexisting consumption is described in Sect. 4.1.1,“Energy Use Review.”

The inspection by the A/E will consist ofvisual observation of energy systems andcomponents as described in Sect. 4.1,“Inspection,” and the completion of theinspection report forms included in Appendix A.It is anticipated that a qualified inspector—onewho has a technical background and is familiarwith energy-efficiency techniques and tools (butis not necessarily an energy specialist)—cancomplete approximately two inspections perday. For units in which the retention of theexisting air distribution duct system and/or amajor portion of the interior is anticipated, adetailed evaluation by an inspector qualified inthe use of a blower door is required. Theprocedures to follow and detailed inspectionforms are provided in Appendixes C, D, E, andF of this guide.

An inspection of existing housing units foreach type being revitalized is required toadequately define the areas to be addressedduring revitalization. Table 2.1 shows howmany buildings must be inspected in relation tothe number of buildings to be revitalized. Thedata from the inspection reports will form thebasis of decisions made during the analysis andselection of revitalization options. Theinspection process identifies current efficiencylevels and flaws and barriers preventing furtherefficiency improvements.

Section 4.2, “Analysis and Selection,” willhelp the A/E select the appropriate kinds andlevels of energy efficiency for each type of unitin the project. This section guides the A/E indetermining whether and to what extentefficiency levels should be improved, theefficiency measures to consider, and the meansof achieving improvements.

AREAS TO BE ANALYZED

The following elements impact the energyefficiency of Air Force family housing and shallbe addressed by the A/E in the analysis phase ofthe process.

Building Envelope

The entire existing envelope and anyadditions will be analyzed, thermal boundarieswill be defined, and insulation levels for theentire boundary will be determined andspecified for the specific climate and fuel cost.Air-leakage locations and bypasses in the

Table 2.1. Inspection sampling requirements

Number of buildings of aspecific type

Number of buildings tobe inspected

1 1

2–50 2

51–75 3

76–100 4

101–125 5

126–150 6

151–175 7

>175 8


building envelope that allow conditioned air tomove directly out of the house, often associatedwith “holes” in the envelope, will be identifiedfor sealing. Appropriate quality energy-efficientreplacement windows and doors will beidentified and specified when replacement unitsare called for in the revitalization project or ifeconomically justified.

Heating and Cooling System

The proper heating and cooling equipmentwill be determined for the climate, fuel type andcost, and house load if replacement units arecalled for in the revitalization project or ifeconomically justified. A life-cycle costapproach will be used to decide whether toreplace equipment and what new equipment toselect. Insulation levels for uninsulated ductsthat are located outside the thermal boundary (inattics, crawl spaces, or unheated basements) willbe identified, and leaking ducts will beidentified for repair or replacement.

Domestic Water Heating System

Water heating equipment not identified forreplacement as part of the revitalization will beevaluated for replacement during revitalizationbased on its energy efficiency. The life-cyclecost impact of alternative fuels (electric andnatural gas) will be evaluated and the leastcostly selected. The efficiency differencesamong available equipment will be evaluated ona life-cycle cost basis. Water conservationopportunities will be identified and included inthe revitalization to the extent that they are costeffective.

Major Appliances

Appliances not identified for replacement inthe revitalization project will be evaluated todetermine if replacement based on improvedenergy efficiency is economically justified. Thelife-cycle cost impact of alternative fuels(electric and natural gas) will be evaluated andthe least costly selected. The efficiency

differences among appliances will be evaluatedon a life-cycle cost basis and the one with theleast life-cycle cost selected.

Lighting

Replacing old lighting systems will usuallybe part of a revitalization. However, whenreplacing the existing lighting system is not partof the revitalization, an energy-efficient lightingstrategy will be evaluated to determine if partialor complete system replacement is economicallyjustified.

Site Improvements

Existing and future site improvements(landscape and pavement) will be evaluated fortheir potential impact on the energyperformance of the dwelling units. Designs thatminimize energy consumption will be specifiedwhenever cost effective.

DOCUMENTATION OF ANALYSIS

The analysis process (Forms G.1 to G.17,Appendix G) will be completed and provided tothe program manager for review and approval.

STANDARDS FOR REVITALIZATION

The following manuals are Air Forcestandards that govern the design of new familyhousing: Air Force Instruction 32-6002, datedMay 12, 1994, and Air Force Family HousingGuide for Planning, Programming, Design, andConstruction dated December 1995. Theprescriptive standards and criteria listed in thesemanuals are applicable to “all buildings of newconstruction or substantially altered buildingenvelopes.” They shall be consulted in thoseportions of revitalization projects in which

• new construction replaces or adds to theexisting building envelope (e.g., buildingadditions),

• access is provided (for other thanenergy-efficiency reasons) to normallyinaccessible portions of the existing


building envelope, allowing the changes tomeet prescriptive standards and to be madecost effectively (e.g., removal of the interioror exterior finish of a wall because ofdeteriorated conditions or electricalupgrade, permitting increased levels of wallinsulation), or

• the total cost of modifying the existingenvelope (demolition, modification, andrestoration) to prescriptive standards can beshown to be cost effective based on energysavings alone.

The U.S. Department of Commerceannually updates the present worth factors to beused in military life-cycle cost analyses. Annualfigures are published in Present Worth Factorsfor Life-Cycle Cost Studies in the Department ofDefense (S. R. Peterson, NISTIR 4942-2).Factors presented in this Guide are for 1995.Revised factors must be obtained for futureyears from the reference.

BASIS OF SELECTION

Three different bases for selectingefficiency options are likely to be encounteredin revitalization projects and are as follows:

1. A revitalization option is selected for otherthan energy-efficiency reasons. Thesereasons could include deterioration ofbuilding components (e.g., new double-panewindows to replace worn out windows),equipment that has reached the end of itsuseful life [e.g., a new 80% annual fuelutilization efficiency (AFUE) furnace toreplace an existing 20-year-old unit], orother aesthetic or functional reasons (e.g.,upgrading space to conform to currentprivate-sector practices).

2. The incremental cost of a higher efficiencyreplacement option compared with thestandard replacement option is costeffective. An example is replacing aworn-out furnace with a high-efficiency

(92% AFUE) furnace rather than aminimum efficiency (80% AFUE) unitbecause the incremental cost increaseprovides benefits that are cost effective overthe life of the furnace.

3. A revitalization measure is selected on thebasis of energy conservation potential and iscost effective. Examples are addinginsulation to an uninsulated wall, convertingan existing electric water heater in goodcondition to a new gas heater, or installing anew high-efficiency furnace even thoughthe existing unit has remaining life.

For purposes of this guide, the total projectenergy savings does not depend on which basisis used to determine to replace a component. Forexample, the savings of new windows is thesame whether the windows were replacedbecause they were worn out or because theywere inappropriate for the climate. The totalsavings generated will be related only to thedesign of the new windows compared with thewindows that were replaced.

The cost of installation and the energysavings to be used for life-cycle analysis,however, will depend on which basis is used todetermine to replace a component. For example,if the windows need replacement because of thecondition of the old windows, then the cost andenergy comparisons should be based only on theincremental cost and energy savings of a newefficient window over a new basic window.However, if the existing windows are in goodshape but should be replaced for energy reasons,the total energy savings should be used and thecost of an upgraded window should include thecost of the new window, demolition anddisposal of the old window, and installation ofthe new one.

This guide contains the information neededto make cost-effective revitalization decisionsbased on climate, fuel cost, and the A/E’sestimate of installation cost. The procedures aredetailed in Sect. 4.2, “Analysis and Selection.”


RESOLUTION OF CONFLICTINGCRITERIA

Conflicting criteria will be resolved in thefollowing order: (a) adhering to the project’sStatement of Work, (b) adhering to the

appropriate Air Force standards manualspreviously cited, and (c) selecting the criteriathat are shown to be most cost effective asapplied to the specifics of the project.


2.4 Specification of Energy-Efficiency Options

Use existing commercial/industry standardsand specifications as identified in the Statementof Work and applicable Air Force standardsmanuals cited in Sects. 2.2 and 2.3 for routineequipment and materials such as furnaces, airconditioners, water heaters, insulation, etc.These are examples of components that areroutinely available in the marketplace and forwhich existing specifications are referenced.

Use the following additional or supplementalspecifications from this guide (provided inChap. 5, “Specification of SelectedEnergy-Efficiency Options”) for areas notappropriately covered in existing specifications:infiltration reduction, windows and doors,heating and cooling equipment, and airdistribution systems.


3Chapter

DESIGN, ANALYSIS, AND SELECTIONOF OPTIONS FOR NEW HOUSING

3.1 Overview................................................................................... 3-13.2 Selection of ECMs Using COSTSAFR ..................................... 3-23.3 Details of the Point System Work Sheet................................... 3-43.4 Example of Point System Work Sheet...................................... 3-83.5 Design Considerations.............................................................. 3-17

3.1 Overview

This chapter provides information to theA/E about energy-saving considerations thatshall be included as an integral part of thedesign effort for new construction. Theenergy-efficiency measures identified in thisguide are conventional in approach in that theyuse proven, cost-effective, off-the-shelfmaterials and hardware that will producesignificant energy savings. Production of anenergy-efficient home does not requireexceptional materials or construction skills.However, attention to detail and emphasis onquality building practices are essential to theproject’s success and will have a majorinfluence on its energy consumption and costs.

This chapter outlines a two-part process forthe design of an energy-efficient housing unit.

The first part involves the selection of energyconservation measures (ECMs) and features forthe unit. This selection will be based partly onefficiency levels selected using a point systemwork sheet established by the COSTSAFRprogram as outlined in Sect. 3.2, “Selection ofECMs Using COSTSAFR.” ECMs for elementsof the housing unit not addressed byCOSTSAFR are selected as outlined inSect. 3.5, “Design Considerations.”

The second part of the design process fornew construction involves the properspecification of all ECMs to ensure correctinstallation. Specifications are discussed inSect. 3.5, “Design Considerations,” andprovided in Chap. 5, “Specification of SelectedEnergy-Efficiency Options.”

DESIGN, ANALYSIS, AND SELECTION 3-1

3.2 Selection of ECMs Using COSTSAFR

The analysis and selection of ECMs for newor replacement Air Force family housing unitsusing COSTSAFR should follow the followingsix steps.

STEP ONE: REVIEW POINT SYSTEMWORK SHEETS PROVIDED

The point system work sheet established bythe COSTSAFR program is unique for eachhousing type being considered. A work sheet foreach housing type to be designed will beprovided to the A/E as part of the Request forProposal or Statement of Work for the project.The work sheet provides three important itemsfor use in the design of each new housing type:

• the minimum number of points a housing

design must meet to ensure that it is energyefficient,

• the means to calculate the points for aproposed housing design, and

• “optimum” cost-effective energy-efficiencylevels for that particular housing type. The term “points” relates inversely to

energy consumption, that is, the higher thepoints, the lower the expected energyconsumption of the housing unit.

Select ECMs that earn credit in the pointsystem. ECMs include insulation levels,window type and area, infiltration levels,heating and cooling equipment types andefficiencies, and water-heating type andefficiency. The cumulative points from allECMs must equal or exceed the minimum pointtotal provided on the last page of the work sheet.

The optimum efficiency levels identified inthe work sheets are calculated by COSTSAFRbased on program inputs. These levels may bealtered (above or below) as needed to obtain anappropriate design as long as the total energypackage has a total number of points that equalsor exceeds the specified minimum.

The optimum efficiency levels andminimum points for a specified size of housingunit are summarized on one page by the CAPSprogram. CAPS also estimates the energyintensity of the optimized design in units ofthousands of Btus per square foot.

STEP TWO: VERIFY MANDATORYENERGY REQUIREMENTS

Air Force energy-efficiency standardsidentified in Sect. 2.2, “Design, Analysis, andSelection of Options for New Housing,” andpertaining to the various energy-related housingelements addressed by COSTSAFR will alreadybe integrated into the point system work sheetsby the personnel running the COSTSAFRprogram (see Sect. 1.4, “Preparation ofInstructions to the Architect/Engineer”).Additionally, personnel running COSTSAFRwill integrate unique project requirementsaffecting energy use into the work sheets to theextent possible. Some project requirements,such as fuel choice, may have to be factored intothe design by the A/E as subsequently outlined.

STEP THREE: DESIGN PROTOTYPES

Develop a conceptual energy designpackage keeping in mind the minimum pointsand optimum efficiency levels identified in thework sheets, project specifications that have notalready been integrated into the work sheets,and the energy conservation measures describedin Sect. 3.5, “Design Considerations,” andSect. 4.2, “Analysis and Selection.” Choose thecombination of energy-saving techniques thatare most compatible with the project designapproach and cost goals. Cost effectivenessshould be the major consideration whenchoosing the mix of energy-saving features.

3-2 DESIGN, ANALYSIS, AND SELECTION

STEP FOUR: COMPLETE POINTSYSTEM WORK SHEETS

Once a conceptual energy design packagefor each unit type has been developed, completethe point system work sheet for that unit tocalculate the total energy points for the design.A work sheet must be completed for each unittype. Instructions for preparing the point systemwork sheet are described in Sect. 3.3, “Detailsof the Point System Work Sheet.”

STEP FIVE: COMPARE TOTALENERGY POINTS WITH THEMINIMUM REQUIRED POINT TOTAL

The total energy points of each unit typemust be compared to the minimum requiredpoint total for that unit type. If the design doesnot meet the minimum required point total,return to Step Three and develop a new designprototype by changing some of the ECM levelsafter identifying what elements of the unitdesign are causing poor performance. If thedesign equals or exceeds the minimum required

point total, then proceed to Step Six. Higherpoint totals that exceed the minimum requiredpoint total are acceptable if the improved levelof energy efficiency is cost justified or resultsfrom architectural considerations. For example,vinyl rather than aluminum windows may beinstalled to maintain the architecturalappearance of the housing unit even thoughaluminum windows with a thermal break are amore economic choice.

STEP SIX: COMPLETEDOCUMENTATION

When the energy performance requirementsof each unit type have been satisfied, compilethe point system work sheet for each housingunit, and submit the final package to theprogram manager for review and approval. Thepoint system work sheet for each housing type isto be completed to show compliance with theminimum required point total developedspecifically for the unit.


3.3 Details of the Point System Work Sheet

This section provides detailed informationon the procedure to determine compliance withthe minimum required point total established bythe COSTSAFR program for each housing typebeing considered. An example of the pointsystem work sheet is provided in Sect. 3.4,“Example of Point System Work Sheet.” Thepoint system work sheet used to determinecompliance will hereafter be referred to as the“point system.”

DEFINITION OF POINTS

Points are proportional to dollars oflife-cycle energy savings and are relative to theworst (least energy-efficient) level for eachECM. For example, a point total of 53 indicatesthat the prototype being considered generates alife-cycle cost savings of $5,300 in current-yeardollars over the same prototype with theCOSTSAFR minimum-level ECMs. Theabsolute value of the points for any ECM mustbe taken in relative, marginal context. Forexample, the points awarded to foundationmeasures tend to be much higher than the pointsawarded to ceiling and wall insulation becausefloor measures are compared to the veryinefficient minimum level of R-0 (noinsulation). In contrast, the minimum level forceiling and wall insulation is R-11.

Negative numbers are possible for someECMs. For example, heat-absorbing glass(Sect. F on the work sheet) and reflective glass(Sect. G) can have negative points for heatingbecause they negate the potential solar-heatingbenefits of clear glass.

STRUCTURE OF POINT SYSTEM

The ECMs in the point system can bethought of as two independent groups. Theprincipal group includes heating and coolingECMs. This group contains space-conditioningmeasures (work sheet Sects. A through N) andheating, ventilation, and air conditioning

(HVAC) equipment measures (work sheetSect. O). The space-conditioning ECMs consistof the envelope or building-shell measures andare modified in the HVAC section to accountfor HVAC efficiency. Therefore, a change inpoints for any envelope ECM does not directlytranslate to an equal change in total points. Thesecondary group of ECMs includes domestic hotwater (DHW) and refrigerators. Work sheetSects. A, B, C, D, and E must always becompleted, together with work sheet Sect. O andthe DHW group. Work sheet Sects. F through Nare optional, unless otherwise specified.

POINT SYSTEM INSTRUCTIONS

The point system begins with the ceiling,wall, and floor insulation levels (work sheetSects. A, B, and C, respectively). Circle thespecific ECMs incorporated in the design, andcopy the points assigned to these levels into theappropriate space on the work sheet. In worksheet Sect. B, select either the wood-frame wallor the thermal-mass wall measure. The pointsfor the thermal-mass wall ECM depend on theR-value of the insulation, the heat capacity ofthe heavyweight material, and the location ofthe insulation.

Work sheet Sect. D covers infiltration(leakage of air into the building), which is basedon average, tight, or very tight construction.Table 3.1 provides an infiltration point worksheet that must be used to determine infiltrationlevels.

Work sheet Sect. E covers the windowpoints and is based on three factors: windowarea, glazing layers, and sash type. The windowarea is the percentage of window area as afraction of the total conditioned floor area. Forexample, a house with 1000 ft2 that isconditioned and 120 ft2 of window area has a12% window area. The sash type can be eitheraluminum, with or without a thermal break, or


Table 3.1. Infiltration point work sheet

Put a check by the required measures to indicate that they will be included. Circle points for selected optionalmeasures. Add the points and attach this table to the compliance forms. The total points determine the infiltrationlevel.

Required construction measures Check Optional construction measures Points

All doors and windows caulked andweather- stripped.

Cover, caulk, seal, or weather-strip allenvelope joints around windows, betweenwall panels, and between floor/wall andwall/ceiling surfaces.

Cover, caulk, seal, or weather-strip allenvelope penetrations for plumbing, spaceconditioning ducts, electricity, telephone,and utility services.

Provide backdraft or automatic dampers onall exhaust systems.

Optional Construction Measures

Select no more than one of the followingthree measures:

a) Continuous air infiltration barrierinstalled on exterior side of exterior walls,with all joints in the barrier and allpenetrations through the barrier sealed;barrier must cover all joints in the buildingenvelope, from sill to top plate, and mustact as a gasket or be sealed to all windowand door frames.

b) Continuous vapor retarder sheet (e.g.,polyethylene sheeting) installed onheated-in-winter side of exterior walls,sealed at all penetrations (electrical outlets,window and door frames); retarder must becontinuous over all envelope joints andjunctions (corners, band joist, interiorpartition meeting exterior wall, etc.) andmust be lapped and sealed with acousticalsealant at all retarder joints; electricaloutlets and switches in exterior wall mustbe gasketed with foam inserts, or of aproven airtight design.

c) Air infiltration barrier (item a above)plus a vapor retarder sheet (item b above).

____

____

____

____

Points

13

13

20

All electrical outlets and switches in exterior wallsgasketed with foam inserts (0 points if credit takenfor an air infiltration barrier or continuous vaporretarder).

Interior partitions, duct drops, and cabinet soffitsframed after installation of continuous vaporbarriers (e.g., polyethylene sheeting) andcontinuous drywall on ceiling.

No recessed lighting fixtures installed in ceilingsbetween conditioned or unconditioned spaces, orspecification of “IC” (insulated ceiling) recessedlight fixtures.

Windows and doors certified to have infiltrationrates equal to or less than 0.25 cfm per foot ofcrack (windows) or per square foot (doors).

Windows and doors certified to have infiltrationrates from 0.26 to 0.34 cfm per foot of crack(windows) or per square foot (doors).

Windows and doors certified to have infiltrationrates from 0.35 to 0.5 cfm per foot of crack(windows) or per square foot (doors).

Storm doors and windows provided.

Specification of nonducted space conditioningsystem (e.g., electric baseboard, hydronic), orlocation of all ductwork within conditioned space.

Sealed and taped ductwork specified for all supplyand return air ducts located in unconditionedspace, if a duct system is used.

Specification of noncombustion heatingequipment (electric furnace or heat pump) orsealed combustion furnace (for gas or oil heatingsystems), or location of combustion furnace inunconditioned space.

TOTAL POINTS =

Circle applicable infiltration levelAverage: less than 16 pointsTight: 16 to 35 pointsVery Tight: 35 points plus heat exchanger

1

4

3

3

2

1

1

10

5

2

____


wood/vinyl (vinyl is considered to be equivalentto wood).

Work sheet Sects. F through L covervarious window measures that can then be usedto modify the absolute contribution of thewindows to the point total. Window area,glazing layers, and sash type in these sectionsmust be consistent with those selected in worksheet Sect. E. The sun-tempered measure inSect. I accounts for window orientations morefavorable than the default, which assumes thatwindows are equally distributed. Work sheetSects. J, K, and L represent points for movablenight insulation for windows. Work sheetSect. M is for sun spaces, and work sheetSect. N is for light-colored roofs. Work sheetSect. I should be used infrequently becausehousing units of the same type have multipleorientations when built, and work sheet Sects. J,K, L, and M should be used infrequentlybecause moveable insulation and sun spaces arenot usually practical for military family housing.A roof (or its shingle) must have a ratedreflectance value of 0.3 or greater to beclassified as a light-colored roof. This cantypically be met only by light-colored metalroofs and white-shingle roofs in an area notsubject to mildew growth.

In work sheet Sect. I, the points aredetermined for sun-tempered designs bycompleting three equations for both heating andcooling. Note that this section is completed onlyif the window orientation is not divided evenlyamong the four cardinal directions. In

Equation A of work sheet Sect. I, the area ofeach orientation is entered as a fraction of thetotal window area. For example, if 20% of thewindows are on the north side, then the entryabove “N” is 0.20. In Equation B of Sect. I, thequantity “X”, calculated in Equation A, ismultiplied by the total window area percentageand the shading coefficient. The total windowarea percentage is entered as a fraction of one.For example, if the total window area is 10% ofthe heated floor area, then the entry above“%AREA” is 0.10. If actual shading coefficientsare not available, use the data in Table 3.2.Equation C of work sheet Sect. I uses thequantity “Z” from Equation B in two differentlocations. By using this equation, the heatingand cooling points for the sun-tempered sectionare determined.

Work sheet Sect. O uses the heating andcooling total points from work sheet Sects. Athrough N, Space Conditioning Total, inequations for the HVAC equipment todetermine the Total Heating and CoolingPoints. The heating and cooling points fromSects. A though N of the work sheet are addedand entered at the middle of page 5 of the worksheet to get a separate total for heating andcooling. In work sheet Sect. O, first enter theappropriate space-conditioning total in theparentheses in step A (heating) and step C(cooling). Complete the equations in steps Aand C, and insert the results in the parenthesesabove the letters “X” and “Y” in steps B and D,respectively. You must also enter the efficiency

Table 3.2. Window shading coefficients

Layers

Glass type Single Double Triple

Clear 1.00 0.88 0.79

Heat absorbing 0.77 0.64 0.56

Reflective 0.40 0.31 0.30

Low-E — 0.78 0.70


of the heating and cooling equipment in steps Band D. Use the AFUE, HSPF, and SEER valuesfrom the Federal Energy Label, which isrequired for all residential furnaces and airconditioners, for the proposed equipment.

The A/E may choose any of the differenttypes of heating equipment listed in step B. It isrecommended that all allowable equipment betried and the heating points compared.Equipment with higher fuel costs will oftenmake it extremely difficult to meet theminimum required point total.

The numbers obtained from steps B and Dfor both heating and cooling in work sheetSect. O are the Total Heating and CoolingPoints and are rewritten at the bottom of page 5of the work sheet. The Total Heating andCooling Points on the bottom of page 5 of thework sheet are the only points from work sheetSect. O.

The DHW and REFRIGERATOR/FREEZERS point systems on page 6 of thework sheet are independent of all other ECMs.The equations for the DHW heaters are based onthe number of bedrooms in each unit. Enter theenergy factor from the Federal Energy Label ofthe proposed water heater in the blank above“EF” on the appropriate line, and perform thenecessary calculation to determine the points forthe DHW heater. Enter the rated annual energyconsumption from the Federal Energy Label ofthe proposed refrigerator/freezer in the blank

above “kWh/year,” and perform the necessarycalculation to determine the points for therefrigerator/freezer. Add both points todetermine the “Total DHW Heater andRefrigerator/Freezer Points.”

To determine the Total Points on page 7 ofthe work sheet, copy the heating point total andthe cooling point total from the bottom ofpage 5 into the appropriate blanks. Also, copythe Total DHW/RFR from page 6. Calculate theTotal Points by adding the three values. TheTotal Points must be equal to or greater than theMinimum Required Point Total shown justbeneath the Total Points. Note that the requiredpoints vary with the number of bedroomsbecause of varying hot water usage.

The Estimated Unit Energy Cost over25 years is calculated and appears at the bottomof page 7. Enter the conditioned floor area insquare feet. The Estimated Unit Energy Cost isshown in hundreds of dollars.

INTERPOLATING BETWEENENERGY CONSERVATIONMEASURES

ECMs that fall between levels in the pointsystem can be awarded points through standardinterpolation techniques. For example, an R-16wall is the average of the point values for R-13and R-19.


3.4 Example of Point System Work Sheet

An example of the COSTSAFR pointsystem work sheet to be provided to and used bythe A/E is provided on the following pages. Theone page summary output obtained from CAPSis also provided at the end. This example is for asingle-story ranch-style house located at Tyndall

AFB, Florida. The values on the work sheetsprovided to the A/E will vary from this examplebecause of differences in climate, fuel cost, fuelselection, construction cost, housing type,foundation type, and heating and coolingequipment.


Tyndall AFB, FL Single Story Ranch Houses3 BedroomsBUILDING CATEGORY SELECTED LEVELHEATINGCOOLINGA: Ceiling Insulation R-19 2.2 1.6B: Wall Insulation R-11 0.0 0.0 Wood Frame Thermal MassC: Floor Type/Insul Slab on Grade R-5_2FTD: Infiltration TIGHT 5.4 1.9E: Window Area/Type 12% ALUMINUM DOUBLEF,G,H: Tinted or Low-E 0.0 0.0I: Sun Tempered 25%N 25%E 25%S 25%WJ,K,L: Moveable Insul 0.0M: Sunspaces 0.0N: Dark Roof Color 0.0O: HVAC Equipment NatGas 0.75 SEER=10.00DHW Equipment Gas Energy Factor=0.621Refrig/Freezer kWh/yr=800.5-----------------------------------------------------------Complies-----------------------------------------------------

----DWH/RFR HEATING COOLINGPROPOSAL REQUIRED

YEARLY KBTU/SQFT: 29.9 + 15.7+ 9.9=55.5-----TOTAL POINTS: 7.3 +37.5+35.9=80.7 79.0

Estimated life-cycle energy cost for 1200 square foot house is $10139


3.5 Design Considerations

Providing an energy-efficient home includesappropriately addressing four key areas in thedesign process: building envelope, heating andcooling system, hot water system, and otherenergy-consuming devices. Meeting theminimum required total points using the pointsystem work sheets addresses only the selectionof some elements of each of these areas. Otherelements must also be properly selected in eacharea, and all elements must be properlyspecified to ensure quality installation.

BUILDING ENVELOPE

The heating and cooling energyconsumption of a home is significantly affectedby the thermal performance of the buildingenvelope. An energy-efficient building envelopeincludes the following characteristics.

A Tight Building Envelope

Infiltration and exfiltration through a poorlyconstructed building envelope can account for asignificant portion of a home’s heating andcooling energy consumption.

All detached housing units must meet theair-leakage performance criteria specified inSect. 4.2.6, “Infiltration.” Although the meansof meeting the air-leakage criteria are left to thecontractor, infiltration-reduction characteristicsassumed for the housing unit design and used inthe point system work sheet (Table 3.1) must bespecified for installation. Common air-leakageproblems as described in Appendix D must beavoided, and careful sealing of buildingenvelope penetrations must be specifiedfollowing the techniques described in Sect. 5.2,“Infiltration Repair Specifications andConstruction Tips.” Compliance with theair-leakage criteria shall be verified throughperformance testing of a randomly selectedsample of housing units, as provided inSect. 5.3, “Infiltration Performance Testing of

Housing Units,” and the testing procedurespecified in Appendix C.

Air-leakage performance criteria forattached housing cannot be specified becauseair-leakage criteria and test procedures for thistype of housing have not been generallydeveloped or accepted. Infiltration-reductioncharacteristics assumed for the housing unitdesign and used in the point system work sheet(Table 3.1) must be specified for installation.Common air-leakage problems as described inAppendix D, as well as air leakage betweenattached units, must be avoided in the design.Careful sealing of building envelopepenetrations must also be specified followingthe techniques described in Sect. 5.2,“Infiltration Repair Specifications andConstruction Tips.”

Proper Insulation

Insulation types and thicknesses wereselected using the point system to meet energygoals. Specify careful installation of insulationto ensure complete, unbroken coverage of thefull building envelope. See Sect. 4.1.4,“Thermal Boundary Identification,” andSect. 4.2.2, “Thermal Boundary,” for adiscussion of the definition of the thermalboundary and common gaps found in Air Forcefamily housing.

Energy-Efficient Windows and Doors

Energy-efficient windows that minimizeheat loss and infiltration were selected under thepoint system. For additional information on theselection of proper windows, see Sect. 4.2.8,“Windows.” Sect. 5.4, “Windows and Doors,”provides a recommended specification forwindows and glass exterior doors. Exteriordoors must conform with Air Force standards(see Sect. 4.2.9, “Doors”), have low infiltrationratings, and be of solid wood or metal with aninsulated foam core.


Appropriate Use of Passive SolarApplications and Natural Ventilation

Passive solar applications allow solarradiation to enter the building’s thermalenvelope in the winter and exclude it in thesummer. Applications include site planning,window shading, and landscaping as describedin Sect. 4.2.19, “Site Improvements.” Naturalventilation, including whole-house fans, alsomerits consideration for energy-efficient designin moderate climates.

HEATING AND COOLING SYSTEM

Heating and cooling systems directlyconsume 30 to 45% of the overall energyconsumption of a home. An energy-efficientsystem includes proper selection and installationof heating, cooling, and air distribution systems.Cost-effective selections of fuel type, heatingand cooling system types, and systemefficiencies were performed using the pointsystem. Properly sized equipment must bespecified by performing load calculations asdiscussed in Sect. 4.2.13, “Heating and CoolingEquipment Sizing and Location.” This sectionalso discusses system location criteria that mustbe considered and addressed in the design. Inaddition, Sect. 5.5, “HVAC Equipment,”provides information for the specification andcommissioning of heating and coolingequipment.

Air distribution systems shall be designedfollowing the new ductwork proceduresspecified in Sect. 5.6, “Air Distribution SystemRepair and Construction Specifications,” andmust meet the air-leakage performance criteriaspecified in Sect. 4.2.15, “Air DistributionSystem.” Common duct problems as describedin Appendix F must be avoided in the design.Careful sealing of ducts must be specifiedfollowing the techniques described in Sect. 5.6.Compliance with the air-leakage criteria shall beverified through performance testing of arandomly selected sample of housing units asprovided in Sect. 5.7, “Air Distribution System

Performance Testing,” and the testing procedurespecified in Appendix E.

DOMESTIC HOT WATER SYSTEM

The DHW system directly consumes 20 to30% of the overall energy consumption of ahome. Cost-effective selections of fuel type andsystem efficiency were performed using thepoint system. The fuel type selected by the pointsystem should be consistent with thecost-effective fuel as described in Sect. 4.2.16,“Domestic Water Heating System.”Specifications concerning insulation andinstallation to minimize the DHW energy usageas described in this section must also befollowed. In addition, flow-limiting showerheads must be specified.

OTHER ENERGY-CONSUMINGDEVICES

The remaining 30 to 40% of home energyconsumption is attributable to numerous devicesfound throughout the home. Major appliancesand lighting consume the bulk of this energyand are included in new construction projects.Appliances include both government-furnishedand occupant-furnished items. Refrigerators andranges are provided by the Air Force and aremajor energy consumers. Dryers, washers, colortelevisions, and other appliances are typicallyoccupant furnished and are beyond the scope ofthis guide.

Cost-effective selection of the refrigeratorwas performed using the point system. Inaddition to the cost-effective fuel selection forranges, all other major appliances installed bythe project should be selected in accordancewith Sect. 4.2.17, “Exhaust Systems andAppliances,” based on their certified applianceefficiency standards labels. Similarly,energy-efficient lighting should be specifiedwhen consistent with project cost and energyobjectives. See Sect. 4.2.18, “Lighting,” forlighting recommendations.


4Chapter

INSPECTION, ANALYSIS, ANDSELECTION OF OPTIONS FORREVITALIZED HOUSING

4.1 Inspection ................................................................................. 4-14.2 Analysis and Selection.............................................................. 4-16

4.1 Inspection

Section 4.1 provides the informationrequired to appropriately inspect existinghousing units from an energy-efficiencyviewpoint using the forms provided in AppendixA. Refer to Sect. 2.3, “Inspection, Analysis, andSelection of Options for Revitalized Housing,”to determine the number of individual housingunits that need to be inspected.

Section 4.1 identifies both what to look forand how to note the findings for later use with

Sect. 4.2, “Analysis and Selection.” It isintended to supplement, not replace, otherrevitalization inspection procedures thatevaluate the unit’s condition, adequacy, andconformance to applicable regulations. Theseother inspections should include identificationof moisture damage, moisture leaks, pestproblems, and other elements that need to becorrected before building energy efficiencyimprovements are made.

INSPECTION, ANALYSIS, AND SELECTION OF OPTIONS 4-1

4.1.1 Energy Use Review

An important step in inspecting familyhousing to be renovated is comparing thecurrent energy consumption of the housing unitswith the “energy budget” calculated by theCAPS program. A one-page summary sheet ofoutput by CAPS (see Sect. 3.2, “Selection ofECMs Using COSTSAFR”) will be provided tothe A/E as part of the Request for Proposal orStatement of Work for the project. The energybudget is provided in thousands of Btus persquare foot of living area per year and reflectsoptimum energy consumption for a comparable,newly built unit.

Data that will be used by the A/E toestimate the current energy consumptionintensity of the housing units to be revitalizedcan be inaccurate. Additionally, the actualconsumption data include energy use forbase-load activities such as cooking and lightingthat are not included in CAPS values. Therefore,the comparison between current energy use andthe CAPS energy budget serves only as a guideto help foresee the magnitude of energydeficiencies that may exist in the units.Feedback obtained during the inspection itselfwill ultimately determine the degree of energydeficiencies.

Housing units that are 50% over the CAPSenergy budget or that have higher than normal(or expected) energy consumption are likely tohave significant efficiency problems that need tobe identified during inspection and addressedduring renovation. Inspectors should beconcerned if inspection of these housing unitsdoes not reveal efficiency problems sufficient toexplain the high consumption. Higher thannormal energy consumption can be based oncomparisons with other installation energyconsumptions as provided by the DefenseUtility Energy Reporting System (DUERS) oron comparisons with private sector housing inthe same climate.

Actual energy consumption by occupantswho do not pay utility bills can be about 20%

higher than those with a monetary incentive toconserve. Therefore, consumption that is 20%over the CAPS energy budget could still occurin an energy-efficient dwelling that requireslittle retrofit.

The CAPS energy budget combines into asingle value the annual end-use energyconsumption of all fuels (e.g., natural gas, oil,and electricity) consumed by the housing unitfor heating, cooling, domestic water heating,and refrigeration. The conversion factor of3413 Btu per kWh is used to convert electricityconsumption.

Ideally, the annual site energy consumptiondata for just the housing units to be revitalizedshould be used to calculate energy consumptionintensity; however, consumption data areusually available only for all family housing atan installation, rather than for individual units orsmall groups of housing. The energy officer atan installation can usually provide consumptiondata (usually called DUERS data) and housingunit floor areas needed to calculate an energyconsumption intensity. Contacts with theinstallation’s engineering office, mechanical andcivil engineering chiefs, and others may also beneeded.

The accuracy of the energy consumptionand floor area data should be verified when thedata are obtained or at the start of the fieldinspection. Uncertainty in the accuracy ofcurrent energy consumption and floor area datashould be factored into the comparison to theenergy use budget before final conclusions arereached. Conclusions drawn from comparinginaccurate data with energy use budgets will notprovide useful information about the presentenergy efficiency of the housing units.

The accuracy of the energy consumptionand floor area data should be evaluated byperforming the following four steps.

4-2 INSPECTION, ANALYSIS, AND SELECTION OF OPTIONS

1. INSPECT THE METERING SYSTEM

Identify the presence of master meters forfamily housing, and, if present, verify their useto track family housing energy consumption.Inspect the meters to verify their location andoperating status and that they are an appropriatetype. Determine and verify in the field thecalibration schedule of the meters by inspectingcalibration tags. Review and field verify theschematics of gas and electricity distributionsystems to determine if nonfamily housing loadssuch as hospitals, day cares, etc., are monitoredby the “family housing” meter.

2. EVALUATE THE ALLOCATIONFORMULA

Determine the use of an allocation formulato estimate family housing energy use frommetered data. Installations without mastermeters on the family housing use allocationformulae with total installation metered energyconsumption to estimate family housing energyuse. Even at installations that have mastermeters to monitor energy consumption of allfamily housing, nonfamily housing users (e.g.,hospitals) are sometimes connected to thefamily housing meter, requiring an allocationformula to estimate family housing energy use.If a formula is used, the formula should beobtained and evaluated. The evaluation shall

consider the engineering (physical) basis for theformula, availability of supportingdocumentation for the formula, the date theformula was developed, assumptions used indeveloping the formula, and the additions ordeletions of loads since the formula wasdeveloped.

3. REVIEW THE SQUARE FOOTAGEAMOUNTS

Determine the family housing squarefootage value used to normalize the energy usedata before entry into DUERS. Evaluate theaccuracy of this value by researching the lasttime the value was updated, the method used tocalculate the value, the recent history of housingconstruction and demolition at the installation,and whether basement, carport, andinternal/external storage areas are included inthe value.

4. REVIEW DATA ENTRYPROCEDURES

Review the process used to accumulate andinput data to DUERS. This includes determininghow necessary information is collected,calculations are performed, and final values arereported and inputted.


4.1.2 Inspection Process

The elements of the full inspection processare included on the inspection forms found inAppendix A. The forms are designed to guidefield personnel through the inspection process.The forms also document the findings of theinspection for use by those who will analyze theexisting condition and prepare the revitalizationproject plans and specifications.

Some information may be determined eitherbefore or during the inspection from “as-built”record drawings of the units. Drawings,sketches, or housing office records that are notcertified to be as-built should be avoided unlessconfirmed during the inspection.

A reduced level of energy-related inspectionis justified for some items. Items defined by the

military in the revitalization project scope ofwork as “to be replaced,” “to be retained,” or“no change” do not require a detailedenergy-related inspection. Examples includeroofs, doors, furnaces, or air conditioningsystems with no remaining useful life; a recentlyreplaced roof, furnace, or air conditioningsystem with significant remaining useful life;and previously installed replacement windowsin good condition. It will, however, be necessaryto obtain a limited amount of field data for theseitems to be able to estimate their current energyperformance, which is an element in the analysisphase of the project. Field inspection may berequired to integrate these items into the overallrevitalization project.


4.1.3 General Information

Identify the installation at which the unit islocated. Assign a unique identification numberto the housing unit and include it on eachsubsequent form. Document the address of theinspected unit, inspector, affiliation of theinspector, and inspection date.

Identify the type of housing unit inspectedand the presence of shared heating or coolingsystems. Units should be single-family attachedor detached since the analysis methods used inthis guide are not applicable to multifamily

units. If a unit is single-family attached, indicatehow many housing units are attached.

Calculate the total gross floor areas andgross floor areas that are intentionally heatedand air conditioned for each floor of the housingunit. (A definition of an intentionallyconditioned space is provided on the form.)Calculate the total volume of the house interiorusing average ceiling heights and living areasfor each floor. Also, determine the number ofintentionally conditioned stories.


4.1.4 Thermal Boundary Identification

A critical task to be performed during theinspection of the building envelope isdetermining where the thermal boundary of thebuilding structure is currently and where itshould be following revitalization. The thermalefficiency of the boundary can be inspectedonce this determination is made using theguidelines in the following sections. Althoughsimple in concept, identification of the thermalboundary may require some investigative effortin practice.

The thermal boundary separates thecomfort-conditioned (heated and/or cooled)areas of the living unit from the outside or fromnonconditioned spaces such as attics, garages,basements, and crawl spaces. The boundaryreduces the flow of heat between conditionedand nonconditioned spaces from conduction,radiation, and convection (including airinfiltration). The thermal boundary must becontinuous (the entire conditioned volumeenclosed) to be appropriately defined.

A systematic method of identifying thecurrent and proper locations of the thermalboundary is to sketch the living unit’s plan andsection(s) as shown in Fig. 4.1. The thermalboundary of the existing unit should then beidentified on the sketches. Discontinuities in theboundary or areas where the boundary isuncertain should become evident in preparingthis sketch. Building elements (e.g., walls,ceilings, and foundations) that make up thethermal boundary will need to be inspected todetermine their current levels of thermalefficiency.

Windows, skylights, exterior walls, exteriordoors, and ceilings that separate living areasfrom the attic or roof (cathedral ceilings) arereadily identified as part of the thermalboundary. Components that often are

overlooked as part of the thermal boundaryinclude the following:

• floors of second-story overhangs;• knee walls, roof rafters, and truss cords

(collar beam) in finished attics;• “interior” walls used to form a chaseway for

plumbing and ducts that are open tononconditioned spaces; and

• “interior” walls separating attachednonconditioned storage rooms or garagesfrom the living areas. Identifying the location of the thermal

boundary in foundations can be less clearbecause the thermal boundary can sometimes beappropriately placed in several differentlocations. This is especially true with crawlspaces or basements that are not comfortconditioned.

The thermal boundary for a crawl space istypically either the floor separating the crawlspace from the living area of the housing unit orthe walls of the crawl space plus the crawl spacefloor.

The thermal boundary of a basement issimilar to that of a crawl space, although factorssuch as use of the basement (e.g., the presenceof washers and dryers and water pipes, coupledwith an extremely cold climate) must befactored into the determination. For example,the floor separating the basement from theliving area may not be the thermal boundary ifheat loss to the basement is required to preventpipes from freezing. In this case, the appropriatethermal boundary for the housing unit is thebasement walls and floor.

For slab foundations, the slab itself(including the slab edge) is typically the thermalboundary.


Fig. 4.1. Sample sketch showing how to identify the thermal boundary for a housing unit using houseplans and sections.


4.1.5 Insulation

WALLS

Note the type of wall (type of load-bearingstructure), wall exposure, and type of exteriorsiding for each of the exterior wall sectionsmaking up the thermal boundary. Shared wallsbetween duplexes, quad-plexes, and multifamilystructures are not exterior walls. Floors ofsecond-story overhangs are of particularimportance because they are often overlooked.They should be documented with other walls onthis form. Calculate the gross wall area of eachwall section. Document the type and thicknessof existing wall insulation, including whetherinsulated sheathing is present under the siding(especially if vinyl or metal siding has beenadded). If possible, determine whether vapor orinfiltration retarders are present.

An efficient procedure for collecting walland subsequent window and door information isto note appropriate information as a scaledsketch of the walls is developed. Each wallsegment should be numbered or lettered (walllocation) so that wall information entered on theform can be referenced to the sketch and so thatwindows and doors can be identified by wallsegment.

FOUNDATION

Identify the foundation type(s) as eitherbasement, crawl space, or slab. More than onetype may be found in a single housing unit.

Crawl Space

Identify the space conditioning status of thecrawl space, the joist area separating the crawlspace from the floor above (i.e., the “ceiling”area of the crawl space), the perimeter length ofthe crawl space, the height of the crawl spacewalls, and the percentage of this height that isaboveground.

Determine the amount of joist insulation (ifany), the percentage of the band (rim) joist that

is insulated, and the type and thickness of anyinsulation used to insulate the walls of the crawlspace. Also, determine if a vapor retarder ispresent on the floor of the crawl space (coveringthe ground).

Basement

Identify the space conditioning status of thebasement, the area of the ceiling separating thebasement from the floor above, the perimeterlength of the basement, the height of thebasement walls, and the percentage of thisheight that is aboveground.

Determine the amount of joist insulationpresent (if any), the percentage of the band(rim) joist that is insulated, and the type andthickness of any insulation (interior or exterior)used for the walls of the basement.

Slab-On-Grade

Determine the area and perimeter length ofslabs. Identify the type and thickness of existingperimeter insulation.

CEILINGS OR ATTICS

Determine the attic type, area, type andamount of existing insulation, and presence of aradiant barrier for all attic areas adjacent toconditioned spaces. This includes knee walls,collar beams, and other envelope areas createdby finished attic areas. Also, note whether avapor barrier is present.

Check the entrances to the attic areas forinsulation and weather stripping.

Check the attic for adequate blocking (3-in.clearance) of insulation around soffit vents andpossible fire hazards such as recessed lighting,flues, and chimneys. Comment on anynonuniformity of insulation depth caused bypoor installation, wind scouring, etc.

Check the attic for ventilation.


4.1.6 Infiltration

For units that will retain a significantportion of the exterior envelope and currentinterior configuration, an inspection shall beperformed by a qualified inspector equippedwith a blower door to

• measure the amount of total infiltration flow

before revitalization (detached housingonly),

• measure the amount of air leakage in the airdistribution system (if present), and

• identify envelope-leakage locations (e.g.,attic bypasses and unblocked partitionwalls) that must be sealed duringrevitalization. The qualified inspector’s report will provide

the basic information for deciding where theenvelope of the existing housing unit should berepaired or modified to eliminate infiltrationdeficiencies. As discussed in Sect. 4.1.9, “AirDistribution System,” a detailed visualinspection will be performed by the qualifiedblower-door inspector to identify air distributionleaks if the air distribution system is to beretained, and a cursory inspection will beperformed by the A/E auditor if the system is tobe replaced.

The contractor selection guide(Appendix B) is provided to aid the A/E inhiring the services of a qualified blower-door

inspector by specifying the qualifications of thisinspection service. The blower-door inspectorshall measure the total infiltration flow ofdetached housing units following the procedurein Appendix C and perform a detailed visualinspection of the envelope in all housing unitsfollowing the procedure in Appendix D.

Dwelling units that will be “gutted”throughout (including door and windowreplacement) require only a cursory visualinspection by the A/E field personnel. Thepurpose of this cursory inspection is todetermine the impact of infiltration deficiencieson the existing energy performance of thedwelling as described in Sect. 4.2.6,“Infiltration.” The background materialpresented in Appendix D presents basicair-leakage concepts to support this inspection.The cursory inspection is to include

• identification of large gaps around floor

penetrations to basements and aroundceiling penetrations to attics; and

• evaluation of the overall condition of thebuilding envelope [basement/crawl space,main floor(s), and attic] as an infiltrationbarrier. Findings from the cursory inspection are

documented on the infiltration form inAppendix A.


4.1.7 Windows and Doors

WINDOWS

For each window, determine the followingprimary data: number of window glazings;frame type; type and condition of stormwindow; height and width of window; andcondition of weather stripping (i.e., adequate orneeds replacement). Identify the frame materialby inspecting the outside and inside of thesashes to determine if the sash is wood, metal(steel or aluminum), or vinyl. If it is metal,identify (if possible) if it contains thermalbreaks.

Reference windows to the wall segment onwhich they are located, using the wall locationcode. Identical windows on a wall segment canbe listed easily by entering the primary data

once, identifying the number of identicalwindows, and calculating the combined (total)area of all the identical windows.

List all sliding glass doors, french patiodoors, and windows in exterior doors aswindows in this section.

DOORS

For each exterior door, identify the type ofdoor, height, width, and presence of a stormdoor. Determine whether the condition of thestorm door, existing weather stripping, andthreshold are adequate or should be replaced.Reference doors to the wall segment on whichthey are located using the wall location code.


4.1.8 Heating and Cooling Equipment

Inspections of the space-heating andspace-cooling equipment are designed todetermine whether the existing equipment needsto be replaced, retained with modification, orretained with no change based on energyconsiderations. It is assumed that otherinspections performed by the A/E as part of therevitalization effort address safety, repair, andcode issues such as

• electrical cutoff switches,• secured wiring,• asbestos insulation,• adequacy of combustion air,• fuel and gas leaks,• fuel and gas filters and shutoff valves,• chimney and flue clearances,• structural and operating conditions of

chimneys and flues,• heat exchanger condition (e.g., cracks), and• the barometric damper on fuel-oil systems.

A tune-up/commissioning procedure will be

specified for all equipment as part of therevitalization to ensure efficient operation (seeSect. 5.5, “HVAC Equipment”). This proceduremay be performed by inspection personnel or bya hired contractor on a sample of housing unitsas part of the inspection process, either toprovide additional information needed to makethe replacement or modification decisions or toestimate the amount of tune-up work that willhave to be performed.

HEATING EQUIPMENT

Collect information on system type, fueltype, and system age (estimated if the actual agecannot be obtained from facility personnel) ofthe primary space-heating system. Equipmentwill be replaced automatically if the equipmentis older than the following median servicelifetimes:

• 15 years for heat pumps,• 18 years for gas- or oil-fired furnaces, and• 25 years for gas- or oil-fired boilers.

Equipment will also be automatically

replaced if the military has dictated replacementor if the A/E’s other inspections have revealedthe equipment to be nonoperational, unsafe, orat the end of its useful service life.

Collect additional information, as follows,on the primary space-heating system if it willnot be automatically replaced. Identify thelocation of the system. Collect the followingnameplate information: manufacturer, model,input rating, output rating, and rated efficiency.

Note the presence of a pilot light and itscondition (on or off) during the summer forgas-fired systems, and note the presence ofefficiency measures (e.g., vent dampers,intermittent ignition devices, gas power burners,flame-retention oil burners, outdoor temperatureresets) for gas- and oil-fired systems.

Record the type, fuel, and number of anyauxiliary space-heating systems.

COOLING EQUIPMENT

Collect information on system type and age(estimated if actual ages cannot be obtainedfrom facility personnel) for the space-coolingsystems. Equipment will automatically bereplaced if it is more than 15 years old.Equipment will also automatically be replaced ifthe Air Force has dictated replacement or theA/E’s other inspections have revealed theequipment to be nonoperational, unsafe, or atthe end of its useful life.

Collect the following nameplate informationon the space-cooling systems if they will not beautomatically replaced: manufacturer, model,input, output, and rated efficiency. Inspect theoutdoor coil section of central systems todetermine if there is sufficient clear area toprevent recirculation. Note the presence of


landscaping that could contribute to clogging ofthe coil (e.g., bushes, pollen, or leaves).

CONTROLS

Verify the operation of all thermostats. Notethe presence of a “setback” thermostat andwhether it is a type with automatic switchover

between heating and cooling. Identify thelocation of the thermostat. Inspect the wall thethermostat is mounted on to see if the wallcavity is open to the attic or basement/crawlspace, which would allow unconditioned air tocirculate behind the thermostat and lead toincorrect indoor temperature readings.


4.1.9 Air Distribution System

The air distribution system may be retainedwith or without modifications or be totallyreplaced during the revitalization process. Totalreplacement will most likely be needed if asignificant portion of the current interiorconfiguration is being modified (a “gut”rehabilitation), and/or if the space-heating andspace-cooling equipment are being relocated,requiring significant new ductwork. Totalreplacement will also be needed if the existingsystem is damaged, deteriorated, ornonfunctioning and cannot be economicallyrepaired.

Perform a cursory visual inspection of theair distribution system to ascertain the existingconditions. The purpose of this inspection is toallow the impact of the system on the existingenergy performance of the dwelling to beestimated in Sect. 4.2.15, “Air DistributionSystem.” If total replacement is not neededbecause of a gut rehabilitation or equipmentrelocation, then the cursory inspection will alsoallow the A/E field inspector to decide if a totalreplacement is needed because of the existingcondition of the system. Evaluate the conditionof the joint seals, structural integrity, andinsulation in the system (good, fair, or

deteriorated), and record observations on the airdistribution system form in Appendix A. Thebackground material presented in Appendix Fpresents basic duct leakage concepts to supportthis inspection.

When retention of the existing airdistribution system is being considered, aninspection shall be performed by a qualifiedinspector equipped with airflow measuringequipment to measure the amount of air leakagein the air distribution system, identify ductleakage locations that must be repaired and/orsealed during revitalization, identify insulationlevels on the ducts and evaluate its condition,and confirm that continued use of the existingduct system is warranted.

The contractor selection guide(Appendix B) is provided to aid the A/E inhiring the services of a qualified air distributionsystem inspector by specifying thequalifications of this inspection service. Theinspector shall measure the air-leakage rate ofthe distribution system following the procedurein Appendix E and perform a detailed visualinspection of the duct system following theprocedure in Appendix F.


4.1.10 Domestic Water Heating System

Inspection of the domestic water systemfocuses primarily on heating water from thehot-water tank to faucets and shower heads.Water conservation opportunities are addressedto a limited extent. It is assumed that otherinspections performed by the A/E as part of therevitalization effort address safety, repair, andcode issues such as the following:

• pressure relief valves,• flue condition,• adequacy of combustion air,• fuel and gas leaks,• secured wiring,• shutoff valves,• leaks in the hot-water tank and water lines,

and• vulnerability to freezing.

Collect information on system type, fuel

type, and age. If an actual age cannot beobtained from facility personnel, then anestimate can be made from the date ofmanufacture listed on the water heaternameplate (e.g., 1285 is a manufacture date ofDecember 1985). The water heater willautomatically be replaced if it is older than

• 12 years for natural gas or• 18 years for electric.

A water heater will also be replacedautomatically if the Air Force has dictatedreplacement, or if the A/E’s other inspectionshave revealed the system to be nonoperational,unsafe, or at the end of its useful service life.Mineral and rust deposits around the fittings areone suggestion that the tank is approaching theend of its service life.

Collect additional information, as follows,on the water-heating system if it will not beautomatically replaced. Collect the followingnameplate information: manufacturer, model,heating rates, and capacity. Identify the locationof the water heater and the R-value of anyinsulation wrap, if present. Check that the hotand cold water plumbing lines are connected tothe proper fitting on the water tank. Check forheat traps on both the hot and cold waterplumbing lines. Identify the amount ofinsulation, if any, on the hot water plumbingline and the length of piping insulated.

Measure the maximum (full) flow rate of allshower heads. Inspect all sink faucets todetermine if aerators are present. Determine ifwater plumbing lines are located outside theconditioned space of the housing unit. If so,identify those lines that are not insulated orlined with heat tape for protection againstfreezing. Pay careful attention to water lineslocated in utility rooms that are vented to theoutdoors for combustion air.


4.1.11 Other Inspections

EXHAUST SYSTEMS

Verify that all exhaust systems (e.g., rangehood, bathroom fans, dryer vent, and plumbingvents) vent directly to the outside rather than tothe attic or crawl space. Determine whether thebathroom fans, dryer, and range hood havedampered vents; whether the dampers are freemoving; and whether they provide a positiveseal when the exhaust system is off. Check forleaks at the fan and in the ducts for thesesystems.

MAJOR APPLIANCES

The determination to replace or retainappliances other than ranges will be for “otherthan energy reasons” based on other inspectionsperformed by the A/E. Only two energy-relatedinspections need to be performed:

• determine the availability of gas for the

range, and• verify that the space allocated in the kitchen

for the refrigerator allows adequate airflowaround the condenser coils.

LIGHTING

This inspection will determine whether theexisting lighting fixtures will be replaced orretained in service. If the A/E’s contractspecifically calls for replacing all light fixtures(common in revitalizations), the inspectionlikely does not need to be performed.

Assess existing lighting by identifying themounting location of the fixture, lamp type,number of lamps, and total fixture wattage.Identify the type of control. Additionalcomments should be noted concerning the sizeof windows, existing skylights, clerestory

windows (skylights with vertical glazing), andother factors that affect daylighting.

SITE IMPROVEMENTS

Landscaping

Note existing mature landscape materials(e.g., trees and large shrubs), when the plantsoffer (or will offer) shade to the south and westfacades or roofs of the dwelling, or when theycan buffer the dwelling from cold winter winds.Provide exact locations for these plants whenthey occur within the construction boundaries ofa dwelling undergoing revitalization so that sitedesigns can be modified if necessary toaccommodate them and so that they can beprotected appropriately during construction.

Note existing landscape material located inproximity to current or planned exterior airconditioning units (for removal) if its presencemight restrict airflow around the unit in thefuture or contribute to clogging of the outdoorcoil. Note for retention in the final site designany trees that shade planned air conditioningunit locations, without restricting airflow.

Pavement

Carefully evaluate the pavement in closeproximity (approximately 5 ft) to thecomfort-conditioned portions of the dwelling asto its condition and usefulness when it occurs onthe southern and western exposures of thestructure and can reflect significant solar heatonto the structure. Consider removing orrelocating such pavement in the revitalizationprocess. Projects at Air Force bases with little orno summer air conditioning requirements neednot perform this step.


4.2 Analysis and Selection

This section provides information to helpA/E personnel select the most cost-effectiveoptions to reduce energy consumption inrevitalized Air Force family housing. Eachelement of the housing unit that affects energyconsumption is examined to determine whetherthe existing level of efficiency should beincreased or, in the case of replacement, thelevel of efficiency that should be installed. FormG.17 (found in Appendix G) will be completedto document the analysis process for eachhousing unit type to be revitalized, and toindicate the efficiency improvement expectedfrom revitalization.

The A/E will need to know the annualheating- and cooling-degree days for the projectlocation as identified in Engineering WeatherData (AFM 88-29, TM5-785, and NAVFACP-89). Heating- and cooling-degree days formost major Air Force bases in the United Statesare tabulated in Appendix H. The A/E will alsoneed to know the current cost of fuels used inAir Force housing to convert energy savingsinto dollar values that can be compared withcost estimates of energy-efficiency measures.

Estimating installation costs ofenergy-efficient measures is the responsibilityof the A/E because of the varied situations thatcan occur in the revitalization process. Forexample, the cost to install wall insulation in anexisting stud wall would be much lower if thedrywall were being removed for other reasons(such as repair of termite damage or rewiring).Accessible stud cavities can easily be insulatedwith batts; however, enclosed cavities requiremore expensive blown insulation.

The analysis methods used in this guideassume that housing units are single-familydetached or attached structures. Attachedstructures can be duplexes or townhouse-typeunits (units are side by side rather than aboveand below) with separate ground-levelentrances. The methods also assume that heating

and cooling systems are not shared betweenunits.

In general, using the analysis methods, theA/E calculates the annual cost savings for agiven efficiency measure by multiplying annualenergy saving estimates [millions of Btu (MBtu)or kWh] by the installation’s cost for fuel($/MBtu for natural gas and oil or $/kWh forelectricity). The A/E then determines the cost toinstall the measure and calculates two economicindicators: the savings-to-investment ratio (SIR)and simple payback period (SPP).

The SIR is equal to the present value of theenergy savings (annual cost savings multipliedby a present worth factor) divided by the totalinstallation cost. The SPP is equal to the totalinstallation cost divided by the annual costsavings. The SIR must be greater than 1.25 andthe SPP less than 10 for the measure to meetmilitary cost-effective criteria.

The net present value (NPV) of theinvestment is calculated to select one efficiencylevel for a measure when more than oneefficiency level passes the militarycost-effective criteria. The NPV is equal to thetotal installed cost subtracted from the presentvalue of the energy savings. The efficiency levelwith the greatest NPV is selected. Forms forperforming these analyses are found inAppendix G.

The present worth factors presented in thisguide are averaged for the United States and areappropriate for 1995. The factors are presentedregionally and are updated annually by the U.S.Department of Commerce in Present WorthFactors for Life-Cycle Cost Studies in theDepartment of Defense (S. R. Peterson, NISTIR4942-2). Updated factors must be used in futureyears and must be obtained from this reference.The factors are fuel-specific because theyconsider fuel escalation, which varies by fuel.Present worth factors vary among measuresbecause the estimated lifetimes of the measuresvary.


It is important to determine current fuelcosts since fuel costs impact option selection. Ifsignificant increases in fuel cost (25% aboveinflation) or decreases (in response to utility

restructuring) are projected within five years atthe installation undergoing revitalization, theincreases must be factored into the decisionprocess.


4.2.1 General Information

Complete the analysis forms provided inAppendix G of this guide for each housing unittype to be revitalized. If two or more housingunits of a given type were inspected, theinspection results should be synthesized by theperson completing the forms to develop generalrecommendations for all housing units of that

type. Identify the installation at which thehousing type is located. Assign a uniqueidentification number to the housing unit typebeing analyzed, and include it on eachsubsequent form. Document the name and theaffiliation of the person completing the forms.


4.2.2 Thermal Boundary

The building thermal envelope is theprotective shell separating conditioned spacefrom unconditioned space and the outsideenvironment. The desired location of thethermal boundary at the completion ofrevitalization must be clearly defined beforebuilding envelope options are selected. Theexisting boundary identified during the siteinspection should be reviewed and modified asneeded to correct deficiencies. Alterationsduring revitalization that impact the boundarymust also be addressed. Typical alterations thatcould affect the location of the thermalboundary include the following:

• room additions,• conversion of basements from

nonconditioned to conditioned space, and• sealing chaseways for plumbing and

ductwork that penetrate the thermalboundary. Use Form G.2 and the method of identifying

the location of the thermal boundary on housesketches described in Sect. 4.1.4 to develop finaldecisions.

Principal structural elements of the buildingusually define the thermal boundary. Theseinclude windows, exterior doors, exterior walls,and ceilings that separate living areas from theattic or roof (cathedral ceilings). Floors ofsecond-story overhangs and knee walls, roofrafters, and truss chords (collar beams) presentin finished attics are thermal boundaries thatmust not be overlooked.

Define the thermal boundary so thatotherwise “interior” walls used to form achaseway for plumbing and ducts are not part ofit. This can be done by sealing and insulatingthe chaseway where it opens ontononconditioned spaces.

“Interior” walls separating attached storagerooms or garages from living areas usually arethe location of the thermal boundary; definingthe boundary as the exterior walls of these areaseffectively includes them within thecomfort-conditioned portion of the unit.

For slab foundations, the slab itself(including the edge) is the thermal boundary.The thermal boundary for crawl spaces is thefloor separating the crawl space from the livingarea of the housing unit (conventional approach)unless special reasons exist for defining it as thewalls and earthen floor of the crawl space.

The thermal boundary of basementsgenerally is the floor separating the basementfrom the living space. This location will producethe smallest, and least costly to operate,comfort-conditioned space. However, when thebasement is used as a laundry or other normallyoccupied space (e.g., recreation room) or whensevere winter climates would place water pipesand other building equipment in jeopardy offreezing, the thermal boundary extends downthe walls and across the floor of the basement.

Once the thermal boundary is defined,assess the efficiency of each element comprisingthe boundary. Specific recommendations forassessing each element are contained in thesections that follow.


4.2.3 Wall Insulation

New walls added during revitalizationshould be insulated to the current standards fornew construction applicable to the Air Force.

Existing walls may be underinsulated,causing increased energy loss. Determineexisting insulation levels by referring to theobservations recorded during the site inspection.

EXISTING WOOD-FRAME WALLS

Existing wood-frame exterior walls can beinsulated by installing insulation in the studcavities (if none is present) and/or by adding itoutside the studs (under the exterior siding) ifnone is present. Insulation installed in the studcavity can be fiberglass (batts or blown), blowncellulose, or plastic foams. Fiberglass andcellulose installed in the stud cavity of a 2 × 4wall achieves an insulation level of R-11 toR-15. Higher R-values (R-16) can be obtainedusing plastic foams. These foams are in thedevelopmental phase but may be market-readyin the near future.

Insulation can be installed in the studcavities in one of the following ways:

• insulation can be installed when the interior

wall finish (drywall or plaster) is removedas part of the revitalization (primarily battinsulation or wet-sprayed celluloseinsulations);

• loose-fill insulation can be blown throughholes drilled in the interior wall finish, withthe installation holes patched in the drywallor plaster; or

• loose-fill insulation can be blown throughholes drilled from the outside, eitherthrough the exterior wall finish followed bypatching, after sections of the exterior sidingare removed followed by reinstallation, orbefore new siding is installed. Insulation added to the outside of the wall is

usually rigid boards that must be covered by an

exterior finish for protection. An insulation levelof R-5 usually can be achieved with thismethod. This approach is usually consideredwhen new siding is being installed and after studcavity insulation is installed. A combination ofstud cavity and exterior wall insulation wouldyield an overall insulation level of R-19, whichis comparable to that required for newconstruction.

The cost effectiveness of adding wallinsulation to the stud cavity and/or to theexterior (when the stud cavity is alreadyinsulated) under revitalization is determinedusing Figs. 4.2 through 4.5 and Form G.3.

1. The annual space-heating energy savings per

square foot of wall area is obtained fromFig. 4.2 (stud cavity) or Fig. 4.3 (exterior)using the heating-degree days for theinstallation.

2. The annual space-cooling electricity savingsper square foot of wall area is obtained fromFig. 4.4 (stud cavity) or Fig. 4.5 (exterior)using the cooling-degree days for theinstallation.

3. The annual cost savings of the heating andcooling energy savings are calculated inForm G.3 using the installation’s costs forfuel, and the present value of the energysavings are calculated using 25-year presentworth factors. These values are summed toobtain the total annual cost savings and totalpresent value of the wall insulation savings,respectively.

4. The A/E must determine the total cost ofinstalling the wall insulation per square footof wall area. The cost must include allexpenses associated with the improvement,although some expenses may appropriatelybe assigned to other renovation work. Forexample, the total cost of installing exteriorinsulation is limited to materials and thedirect installation cost of the insulationalone if existing siding is slated for


Fig. 4.2. Annual space-heating energy savings per square foot of wall area from installing R-13 insulationin the stud cavity of an uninsulated wood-frame wall.

Fig. 4.3. Annual space-heating energy savings per square foot of wall area from installing R-5 insulationon the exterior of a wood-frame wall with R-13 insulation already installed in the stud cavity.


Fig. 4.4. Annual space-cooling electricity savings per square foot of wall area from installing R-13insulation in the stud cavity of an uninsulated wood-frame wall.

Fig. 4.5. Annual space-cooling electricity savings per square foot of wall area from installing R-5insulation on the exterior of a wood-frame wall with R-13 insulation already installed in the stud cavity.


replacement as part of the revitalization. Animportant factor for the A/E to consider forcavity insulation is whether the interior orexterior finishes will be removed duringrevitalization, providing ready access to thewall cavity.

5. The stud cavity or exterior wall insulationmeets military cost-effective criteria if theSIR is greater than or equal to 1.25 and theSPP is less than or equal to 10. Installinsulation in both locations if both meet thecost-effective criteria. Enter the level of insulation found in the

wall and that to be obtained followingrevitalization on Form G.17. Calculate the totalannual energy savings (space heating combinedwith space cooling), if any, by multiplying thevalues obtained from steps 1 and 2 by the totalwall area to be insulated, multiplying electricitysavings (kWh) by 0.003413 to convert to MBtu,and summing. Enter the total annual energysavings on Form G.17.

EXISTING MASONRY WALLS

Existing masonry walls can be insulated byfurring out the wall interior and adding batt(R-10 to R-15) or rigid insulation (R-5). Spaceloss and cost are the factors influencing thechoice between the two types. For above-gradewalls with exposed concrete block on theexterior or face brick in poor condition,installing rigid insulation (R-5 or R-10) on theexterior may be an attractive option. A varietyof new exterior finishes are available tocomplete the installation and protect theinsulation.

The cost-effectiveness of adding wallinsulation to either the interior or exterior of anuninsulated masonry wall is determined using

Figs. 4.6 and 4.7, Form G.4, and the sameprocedure outlined for wood-frame walls.Again, the total installation cost must include allexpenses associated with the improvement,although some expenses may be appropriatelyassigned to other renovation work. For example,the total cost of installing exterior insulation islimited to materials and direct installation costof the insulation alone if a new exterior (stucco)is to be installed as part of the revitalization.Install the measure with the highest NPV ifmore than one measure meets the cost-effectivecriteria.

Enter the level of insulation found in thewall and that to be obtained followingrevitalization on Form G.17. Calculate the totalannual energy savings (space heating combinedwith space cooling), if any, by multiplying thevalues obtained from Figs. 4.6 and 4.7 by thetotal wall area to be insulated, multiplyingelectricity savings (kWh) by 0.003413 toconvert to MBtu, and summing. Enter the totalannual energy savings on Form G.17.

FLOORS OF SECOND-STORYOVERHANGS

An effective insulating technique forsecond-story overhangs is to blow celluloseinsulation into the overhang cavity throughholes drilled in the exposed soffit until it ispacked tight. This not only insulates the floorbut also effectively seals a major air-leakage site.

Floors of second-story overhangs shouldalways be insulated in this manner if they arenot already insulated because of the dualbenefits obtained (insulation and air-leakagemitigation). Use the technique even if the flooris already insulated if it is warranted forair-leakage mitigation (see Sect. 4.2.6).


Fig. 4.6. Annual space-heating energy savings per square foot of wall area from installing insulation onthe exterior or interior of an uninsulated masonry wall.

Fig. 4.7. Annual space-cooling electricity savings per square foot of wall area from installing insulationon the exterior or interior of an uninsulated masonry wall.


4.2.4 Foundation Insulation

New foundations added duringrevitalization should be insulated to the currentstandards for new construction applicable to theAir Force.

Existing foundations may be underinsulated,causing increased energy loss. Determineexisting insulation levels by referring to theobservations recorded during the site inspection.

Energy losses from uninsulated foundationscan account for 20 to 30% of the space-heatingand space-cooling energy used by an averagemilitary house. Houses built with uninsulatedslab-on-grade foundations are common on AirForce bases. Basements, which are lesscommon, increase the heat loss if the basementwalls or ceilings are uninsulated. Crawl spacesare also used in Air Force housing; they aretypically uninsulated, increasing energy use.

SLAB-ON-GRADE

Polyurethane insulation and extrudedpolystyrene insulation treated with a pest- andwater-resistant coating are the recommendedmaterials for insulating slab-on-gradeperimeters. If the slab perimeter is insulated, noadditional insulation will be cost effective. If noslab edge insulation exists, the cost-effectiveness of adding R-5 perimeter slabinsulation (assumed to cover the 4–6 in. exposedslab edge and extending down 1.5 ft into theground) is determined using Figs. 4.8 and 4.9and Form G.5.

1. The annual space-heating and space-cooling

energy savings per linear foot of perimeterlength are obtained from Figs. 4.8 and 4.9,using the heating-degree and cooling-degreedays for the installation. Note that thecooling savings in Fig. 4.9 are negative.This is because insulation reduces theability of the slab to “lose heat” to theground in the summer, increasing the airconditioning requirements.

2. The annual cost savings of the heating andcooling energy savings are calculated usingthe installation’s costs for fuel, and thepresent value of the energy savings iscalculated using 25-year present worthfactors. These values are summed to obtainthe total annual cost savings and totalpresent value of the slab insulation savings,respectively.

3. The A/E must determine the total cost ofinstalling the slab insulation per linear footof perimeter. This cost must include allexpenses associated with the improvement,although some expenses may beappropriately assigned to other renovationwork. For example, the total cost for slabinsulation would be limited to materials anddirect installation cost of the insulationalone if excavation around the perimeter isneeded as part of the revitalization to fixmoisture problems.

4. The slab insulation meets militarycost-effective criteria if the SIR is greaterthan or equal to 1.25 and the SPP is lessthan or equal to 10. Enter the level of insulation found in the

slab and that to be obtained followingrevitalization on Form G.17. Calculate the totalannual energy savings (space heating combinedwith space cooling), if any, by multiplying thevalues obtained from step 1 by the perimeterlength to be insulated, multiplying electricitysavings (kWh) by 0.003413 to convert to MBtu,and summing. Enter the total annual energysavings on Form G.17.

Seal or caulk the joint between the sill andthe slab before applying insulation. Seal anycracks or openings in the slab edge beforeinstallation.


Fig. 4.8. Annual space-heating energy savings per linear foot of perimeter length from installing R-5insulation on the perimeter of an uninsulated slab foundation.

Fig. 4.9. Annual space-cooling electricity savings per linear foot of perimeter length from installing R-5insulation on the perimeter of an uninsulated slab foundation.


CRAWL SPACE

Crawl space insulation can be located eitherin the floor joist cavities separating the crawlspace from the living area above it or on thecrawl space walls.

When the floor over the crawl space (thecrawl space ceiling) is to be insulated, battinsulation is recommended because of the lowcost, the relative ease of application, and theavailability of kraft-paper vapor retarder facing.Insulation levels of R-11, R-19, and R-30 aretypical. Install batt insulation with the kraftpaper against the subfloor. The insulation is heldin place by a friction fit and is further supportedwith wire hangers. Placing insulation in thislocation could subject uninsulated water pipeslocated in the crawl space to freezing andincrease the energy loss from uninsulated airdistribution ducts located in the crawl space.These problems must be addressed if thisapplication is selected.

An alternative method is to insulate thecrawl space walls. The advantage of thisapproach is that pipes and air distribution ductslocated in the crawl space are included withinthe building thermal envelope, reducing energyloss and freezing potential. The crawl spacewalls can be insulated on the interior or exterior.Batt insulation, rather than expanded orextruded polystyrene insulation, isrecommended for insulation installed on interiorcrawl space walls because of its lower cost andrelative ease of application. The insulation canbe attached to the wall using fasteners designedfor the type of wall material encountered. Rigidinsulation board should be used for exteriorinsulation. Extruded polystyrene isrecommended because of its high R-value, highstrength, and relative ease of application in thislocation.

A vapor barrier must be placed over theground when the crawl space walls are insulatedto reduce the moisture level in the space. Avapor barrier should also be installed on theground when the crawl space ceiling is insulatedas a preventive measure.

Specify insulation levels called for incurrent Air Force standards and a vapor barrieron the ground for new construction or if thecrawl space is currently not insulated in eithermanner. The A/E selects the insulation approachto be used.

Do not install any additional crawl spaceinsulation if the crawl space walls are alreadyinsulated. Also, do not install crawl space wallinsulation if the crawl space ceiling is alreadyinsulated. Perform the following steps usingFigs. 4.10 and 4.11, together with Form G.6, todetermine if additional crawl space ceilinginsulation is justified when ceiling insulation isalready installed.

1. Annual space-heating and space-cooling

energy savings (compared with a crawlspace with no insulation) for three standardlevels of crawl space ceiling insulation(R-11, R-19, and R-30) are provided inFigs. 4.10 and 4.11. The first three steps areto determine the annual cost savings andpresent value of the incremental energysavings from adding crawl space ceilinginsulation to bring the existing level to thestandard levels. The annual heating savingsper square foot of ceiling area is obtainedfrom Fig. 4.10 using the heating-degreedays for the installation. Calculate theincremental heating savings of insulationlevels above the existing level bysubtracting the savings of the existinginsulation from the savings for the higherinsulation levels.

2. The annual space-cooling electricity savingsper square foot of ceiling area is obtainedfrom Fig. 4.11 using the cooling-degreedays for the installation. Determine theincremental cooling savings of insulationlevels above the existing level using themethod described in step 1. Note that thesavings on Fig. 4.11 are negative becausethe insulation reduces the ability of the floorto lose heat to the ground in the summer,increasing the air conditioning requirements.

3. The annual cost savings of the incrementalheating and cooling energy savings are


Fig. 4.10. Annual space-heating energy savings per square foot of crawl space ceiling area frominstalling insulation on the ceiling of an uninsulated crawl space.

Fig. 4.11. Annual space-cooling electricity savings per square foot of crawl space ceiling area frominstalling insulation on the ceiling of an uninsulated crawl space.


calculated in Form G.6 using theinstallation’s costs for fuel, and the presentvalue of the energy savings is calculatedusing 25-year present worth factors. Thesevalues are summed to obtain the total annualcost savings and total present value for eachinsulation level, respectively.

4. The A/E must determine the total cost ofinstalling the incremental amounts of crawlspace ceiling insulation per square foot ofceiling area to upgrade to the higherinsulation levels. For example, the A/Ewould determine the cost to add R-8insulation to achieve a total of R-19 if thecurrent level is R-11. This cost must includeall expenses associated with theimprovement.

5. An incremental amount of insulation meetsmilitary cost-effective criteria if the SIR isgreater than or equal to 1.25 and the SPP isequal to or less than 10. If more than onelevel of insulation meets the cost-effectivecriteria, select the level with the highestNPV. Enter the level of insulation existing in the

crawl space and that to be obtained byrevitalization on Form G.17. If additional crawlspace ceiling insulation is added, calculate thetotal annual energy savings (space heatingcombined with space cooling) by multiplyingthe values obtained from steps 1 and 2 by thecrawl space ceiling area to be insulated,multiplying electricity savings (kWh) by0.003413 to convert to MBtu, and summing. Ifthe crawl space is not already insulated, estimateannual energy savings from ceiling insulationusing values obtained through the methodsoutlined in steps 1 and 2 and using Figs. 4.10and 4.11. Estimate the savings for wallinsulation following step 1 and Fig. 4.10 onlyand still using ceiling areas. Enter the totalannual energy savings on Form G.17.

BASEMENT

Basement insulation can be located either inthe floor joist cavities separating the basement

from the living area above the basement or onthe basement walls.

The floor over the basement (the basementceiling) is the best location if the basement is tobe an unconditioned space (with no registers orradiators). Batt insulation is recommended forthis application because of its low cost, relativeease of application, and the availability ofkraft-paper vapor retarder facing. Insulationlevels of R-11, R-19, and R-30 are typical.Install batt insulation with the kraft paperagainst the subfloor. The insulation is held inplace by a friction fit and is further supported bywire hangers or another bridging system.Placing insulation in this location could subjectuninsulated water pipes and laundry equipmentlocated in the basement to freezing and increasethe energy loss from uninsulated air distributionducts located in the basement. These problemsmust be addressed if this approach is selected.

An alternative insulating method is toinsulate the basement walls. The advantage ofthis approach is that pipes and air distributionducts located in the basement are includedwithin the building thermal envelope, reducingtheir energy loss and freezing potential. Oneway to insulate interior basement walls whenthe basement is a conditioned space is to furrout the walls and create a finished interior wall.The easiest approach is to install batt insulationin the cavities created by 2 × 4 studs and finishthe wall with 1/2-in. gypsum drywall. Analternative is to furr out the walls with 1-in.furring strips, insulate with expanded orextruded polystyrene using a constructionadhesive or special wall fasteners, and thenapply a fire-rated covering such as 1/2-in.gypsum drywall. Before insulation is installedon the walls of a full basement, cracks oropenings along the walls must be sealed.Installation of exterior basement wall insulationas a retrofit is not a cost-effective option.

Specify the insulation levels called for incurrent Air Force standards for new constructionif the basement is not already insulated in eithermanner. The A/E selects the insulation approachto be used depending on the intended use of thebasement.


Do not install any additional basementinsulation if the basement walls are alreadyinsulated. Also, do not install basement wallinsulation if the basement ceiling is alreadyinsulated. Perform the five steps outlined for thecrawl space ceiling using Figs. 4.12 and 4.13,together with Form G.6, to determine ifadditional basement ceiling insulation isjustified when ceiling insulation is alreadyinstalled in this location.

Enter the level of insulation found in thebasement and that to be obtained fromrevitalization on Form G.17. If additionalbasement ceiling insulation is being added,

calculate the total annual energy savings (spaceheating combined with space cooling) bymultiplying the values obtained from Figs. 4.12and 4.13 by the basement ceiling area to beinsulated, multiplying electricity savings (kWh)by 0.003413 to convert to MBtu, and summing.If the basement is not already insulated, estimateannual energy savings from ceiling insulationusing values obtained from using Figs. 4.12 and4.13. Estimate the savings for wall insulationusing Fig. 4.12 only and still using ceiling areas.Enter the total annual energy savings onForm G.17.


Fig. 4.12. Annual space-heating energy savings per square foot of basement ceiling area from installinginsulation on the ceiling of an uninsulated basement.

Fig. 4.13. Annual space-cooling electricity savings per square foot of basement ceiling area frominstalling insulation on the ceiling of an uninsulated basement.


4.2.5 Ceiling or Attic Insulation

New ceilings or attics added duringrevitalization should be insulated to the currentstandards for new construction applicable to theAir Force.

Existing ceilings or attics may beunderinsulated, causing increased energy loss.Determine existing insulation levels by referringto the observations recorded during the siteinspection. Most attic areas in Air Force housinghave some level of insulation.

If the existing insulation is in goodcondition and is uniformly distributed, retain itunless other factors in the revitalization projectdictate its removal.

If there is no insulation, or if therequirements of the revitalization project dictateits removal, install attic insulation to levels(R-value) that conform to the current Air Forcestandard for new construction.

If the attic is an unconditioned space and theattic floor is unfinished, it is usually easiest toadd insulation by blowing in additionalfiberglass or cellulose. If the attic is anunconditioned space and the attic floor isfinished, it is usually easiest to insulate bydrilling holes into the finished floor and blowingfiberglass or cellulose into the cavities.

Perform the following steps using Figs. 4.14and 4.15 with Form G.7 to determine ifadditional insulation should be added to theexisting levels.

1. Annual space-heating and space-cooling

energy savings (compared with an attic withno insulation) for five standard levels ofattic insulation (R-11, R-19, R-30, R-38,and R-49) are provided in Figs. 4.14 and4.15. The first three steps are to determinethe annual cost savings and present value ofthe incremental energy savings from addingattic insulation to bring the existing level tothe standard levels. The annual heatingsavings per square foot of attic area isobtained from Fig. 4.14 using the

heating-degree days for the installation.Calculate the incremental heating savings ofinsulation levels above the existing level bysubtracting the savings of the existinginsulation from savings for the higherinsulation levels.

2. The annual space-cooling electricity savingsper square foot of ceiling area is obtainedfrom Fig. 4.15 using the cooling-degreedays for the installation. Determine theincremental cooling savings of insulationlevels above the existing level in the mannerdescribed in step 1.

3. The annual cost savings of the incrementalheating and cooling energy savings arecalculated in Form G.7 using theinstallation’s costs for fuel, and the presentvalue of the energy savings is calculatedusing 25-year present worth factors. Thesevalues are summed to obtain the total annualcost savings and total present value for eachinsulation level, respectively.

4. The A/E must determine the total cost ofinstalling the incremental amounts of atticinsulation per square foot of attic area toupgrade to the higher insulation levels. Forexample, the A/E would determine the costto add R-8 insulation to achieve a total ofR-19 if the current level is R-11. This costmust include all expenses associated withthe improvement, such as increased atticventilation, baffles (soffit dams), and accesshatches.

5. An incremental amount of insulation meetsmilitary cost-effective criteria if the SIR isgreater than or equal to 1.25 and the SPP isless than or equal to 10. If more than onelevel of insulation meets the cost-effectivecriteria, select the level with the highestNPV. Enter the level of existing insulation and of

that to be obtained from revitalization onForm G.17. If additional attic insulation is being


Fig. 4.14. Annual space-heating energy savings per square foot of attic floor area from installinginsulation on the floor of an uninsulated attic.

Fig. 4.15. Annual space-cooling electricity savings per square foot of attic floor area from installinginsulation on the floor of an uninsulated attic.


installed, calculate the total annual energysavings (space heating combined with spacecooling) by multiplying the values obtainedfrom steps 1 and 2 by the attic area to beinsulated, multiplying electricity savings (kWh)by 0.003413 to convert to MBtu, and summing.If the attic is not insulated, estimate annualenergy savings from new attic insulation usingvalues obtained from following the methodsoutlined in steps 1 and 2, and using Figs. 4.14and 4.15. Enter the total annual energy savingson Form G.17.

Perform air-leakage reduction work (e.g.,sealing attic bypasses and interior partition

walls) and air distribution system repairs in theattic (see Sects. 4.2.6 and 4.2.15) before addinginsulation. Be sure that new or existinginsulation does not block soffit vents byinstalling ventilation baffles (soffit dams) beforeadding insulation as necessary. Also, ensure thatattics are adequately ventilated, especially whenhousing units are air conditioned. Ventilationguidelines are provided in Chapter 2 of the 1993American Society of Heating, Refrigerating, andAir-Conditioning Engineers (ASHRAE)Handbook—Fundamentals.


4.2.6 Infiltration

Detached dwelling units for whichrevitalization entails “gutting” throughout mustmeet prescriptive air-leakage performancecriteria. The air-leakage performance of thesehousing units following revitalization must fallwithin a prescribed range of air changes perhour (ACH) for the conditioned volume of theunit.

The minimum ACH value for a detachedhousing unit is a function of its number ofbedrooms and conditioned floor area and can befound from Table 4.1. The value is based on theminimum ventilation required to provideadequate fresh air to remove indoor pollutantsand moisture from typical residences asspecified in ASHRAE Standard 62-1989,Ventilation for Acceptable Indoor Air Quality.ASHRAE recommends an average ventilationairflow rate from natural infiltration and forced

ventilation (exhaust fans) of 15 cfm peroccupant, or a minimum air change rate of0.35 per hour.

The maximum value for a detached housingunit is either the value obtained from Table 4.2or the minimum value plus 0.3 ACH, whicheveris greater. The value obtained from Table 4.2 isa function of the local climate and is found afterdetermining the infiltration degree-days for thehousing location using Appendix H (Table H.2).The value obtained from Table 4.2 is based onreducing the air infiltration load on the housingunit as specified in ASHRAE Standard119-1988, Air Leakage Performance forDetached Single-Family Residential Buildings.The use of a value 0.3 ACH greater than theminimum value is needed to provide areasonable range that reflects the limits of

Table 4.1. Minimum air changes per hour

Housing unitconditioned floor

area (ft2)

Number of bedrooms

2 3 4 5

600 700 800 90010001100120013001400150016001700180019002000210022002300 and above

0.750.640.560.500.450.410.380.350.350.350.350.350.350.350.350.350.350.35

0.940.800.700.630.560.510.470.430.400.380.350.350.350.350.350.350.350.35

1.130.960.840.750.680.610.560.520.480.450.420.400.380.360.350.350.350.35

1.311.130.980.880.790.720.660.610.560.530.490.460.440.410.390.380.360.35


construction practices in closely controllingbuilding infiltration.

Compliance with this criteria shall beverified through performance testing of arandomly selected sample of housing units. Acompliance testing procedure is provided inSect. 5.3, “Infiltration Performance Testing ofHousing Units,” and shall be specified in theconstruction design package by the A/E. Thisprocedure relies on the measurement procedurespecified in Appendix C. Although the means ofmeeting the air-leakage criteria are left to theconstruction contractor, infiltration-reductionconcepts used in new construction (Table 3.1)are applicable and should be included in theconstruction design package by the A/E.Additionally, common air-leakage problems asdescribed in Appendix D must be avoided, andtechniques needed to seal building envelopepenetrations as described in Sect. 5.2,“Infiltration Repair Specifications andConstruction Tips,” will be needed and shouldalso be included in the construction designpackage by the A/E.

Criteria for attached dwelling units that willbe gutted throughout cannot be specifiedbecause air-leakage criteria and test proceduresfor this type housing are not generallydeveloped or accepted. Infiltration-reductionconcepts used in new construction (Table 3.1)are applicable and should be conveyed in thedesign package by the A/E. Additionally,common air-leakage problems as described inAppendix D must be avoided, and techniques

needed to seal building envelope penetrations asdescribed in Sect. 5.2, “Infiltration RepairSpecifications and Construction Tips,” will beneeded and should also be included in theconstruction design package by the A/E.

Housing units (detached or attached) inwhich a significant portion of the exteriorenvelope and current interior configuration willbe retained during revitalization must have themajor air-leakage deficiencies identified by theblower-door inspection repaired and sealed. Thenatural infiltration rate for detached housingunits was estimated as part of the blower-doorinspection. Little air-sealing work will bespecified if the current infiltration rate is closeto the minimum values identified in Table 4.1 toavoid overtightening the housing unit. Repairspecifications for air-leakage reduction optionsare provided in Sect. 5.2, “Infiltration RepairSpecifications and Construction Tips.”

To document the air-leakage analysis for allrevitalized housing, enter the initial leakage rate(in units of cfm50) obtained from theblower-door inspection of the housing unit onForm G.17. If a blower-door inspection was notperformed, enter a leakage rate of 1800 cfm50 ifa minimal number of major infiltration leakageareas were visible during the field inspection ora rate of 2500 cfm50 otherwise. For the purposeof completing Form G.17, calculate the potentialenergy savings for this measure as follows:

1. Determine the space-heating energy savings

from Fig. 4.16 using the heating-degree

Table 4.2. Maximum air changes

Infiltration degree-days(°F-day)

Maximum air changes per hour

<2250 1.60

2250–3182 1.60

3183–4500 1.13

4501–6364 0.80

>6365 0.65


days for the installation and the initialleakage rate of the housing unit.

2. Determine the space-cooling energy savingsfrom Fig. 4.17 using the cooling-degreedays for the installation and the initialleakage rate of the housing unit. Convert

this value to MBtu by multiplying by0.003413.

3. Sum and enter the energy savings from steps 1and 2 on Form G.17.

Fig. 4.16. Potential annual space-heating energy savings from air-leakage mitigation.


Fig. 4.17. Potential annual space-cooling electricity savings from air-leakage mitigation.


4.2.7 Roofing

The replacement of roofing as part ofrevitalization offers the opportunity to changethe characteristics of the new roof. Changingfrom a low- to a high-reflectivity roof can lowercooling energy consumption on structures withlow levels of attic insulation. Inheating-dominated climates however, thisincreased reflectivity can increase heat energyconsumption, offsetting any cooling savings.

The attic insulation levels achieved inrevitalizing Air Force housing will be wellabove the level at which increased reflectivitysignificantly reduces cooling energyconsumption. Standard shingle colors, despitetheir visual differences, do not have a significantdifference in reflectance. To obtain the increasein reflectivity required to markedly reduceenergy consumption, it would be necessary tocoat the new or existing roof with a reflectivematerial. This process is still under developmentand evaluation and is not currently cost effective.

A roof (or its shingle) with a ratedreflectance value of 0.3 or greater can beclassified as a light-colored roof and may reducecooling energy consumption to a small degree.This can typically be met only by light-coloredmetal roofs and white shingle roofs in an areanot subject to mildew growth.

When ducts are located in the attics ofhousing units in cooling-dominated climates(see locations where heat pumps are generallyallowed in Fig. 4.18 as an indication of acooling-dominated climate), it is desirable toreduce the attic air temperature. This can beaccomplished by proper ventilation and use oflight-colored roofs as previously described. Thisno-cost change may reduce the potential energyloss through the duct system.

Although reducing attic temperature canreduce the potential energy loss through ducts,the key factors in duct performance are that theybe well sealed and appropriately insulated (seeSect. 4.2.15).

Fig. 4.18. Guidelines on use of heat pumps.


4.2.8 Windows

SPECIFICATION OF NEW WINDOWS

Although windows can be a major cause ofenergy loss in homes, they should notautomatically be replaced during a revitalizationproject. In fact, the need for new windows mustbe warranted by the A/E based on architecturalconsiderations rather than on energy savingsbecause energy savings are insufficient to justifythe cost of window replacement (removal of theexisting window plus buying and installing thenew window).

Architectural considerations that warrantwindow replacement include the following:

• existing windows are no longer functional

(have no remaining life),• existing windows no longer fit the

architectural style of the renovated housingunit, or

• wall renovation requires additional windowsor windows of a different size. Keep in mind that many of the original

windows in older Air Force family housing havealready been replaced with energy-efficientunits and may have additional useful life. Otherinspections of the housing unit performed by theA/E as part of the revitalization effort, ratherthan the inspection outlined in this document,are relied on to determine the need for newwindows based on architectural considerations.

In determining the functionality of existingwood windows, especially ones in marginalcondition, keep in mind that wood windows canusually be repaired. Consider evaluating thelong-term maintenance costs before doing so.There are essentially three types of repair:

1. A wood replacement sash can be installed if

the sash is rotted or the joints are loose orbroken. Although a replacement sash cancost as much as a new window, it will savea great deal of labor compared with

removing the entire existing window andinstalling a replacement. Installing areplacement sash requires 2 to 4 hours.Follow the procedure outlined in thissection under “Selection of ReplacementWindow Options” to select the properwindow type.

2. A cabinetmaker or finish carpenter can usuallyrebuild the window in about 4 hours if thewindow is hard to open, is loose (it rattleswhen locked), or doesn’t lock properly butthe wood in the sash, jambs, and sill is stillin good condition. This rebuilding will beless expensive than replacing the sash or theentire window.

3. Repairs can be made by a competent painter ifthe paint on the sash is peeling or the glassis loose but the window opens, closes, andlocks easily. Old paint can be stripped, looseglazing reset, and the sash repainted toextend the useful life of the window. While multipane glazing is a primary

component of an energy-efficient window,single-pane glazing in the existing windowalone is not an appropriate reason to specifyreplacement. Storm windows are available toeconomically enhance the energy efficiency ofexisting single-pane windows, especially in verycold climates. Existing windows that are singleglazed but otherwise functional should beretained unless other reasons warrantreplacement such as excessive condensation oricing on the interior surfaces (although thesolution may be to correct the excessivemoisture problem rather than the window). Theaddition of storm windows to single-glazedwindows should be evaluated as described laterin this section.

Vinyl, fiberglass, and wood are allnonmetallic and relatively nonconductivematerials that are well suited to makingenergy-efficient windows. Vinyl- andfiberglass-framed windows have lower


maintenance characteristics than woodwindows, although many wooden windows areclad with aluminum or vinyl to reducemaintenance. Steel and aluminum (metallicmaterials) are excellent conductors andtherefore intrinsically poor choices for the framematerial of energy-efficient windows. Somemetallic windows have a thermal break (outerand inner sections connected by an insulator)that reduces this problem. Take care during theinspection process that an aluminum-cladwooden window is not mistaken for anall-aluminum window. Although new windowsshould not be specified because existingwindows are inefficiently framed, consider thepresence of inefficient framing in determiningthe functionality and remaining useful life of theexisting window. This includes consideringcondensation and icing problems caused by theframing.

SELECTION OF REPLACEMENT-WINDOW OPTIONS

When new windows are needed or existingwindows need to be replaced because ofarchitectural considerations, specify adouble-glazed low-E window with either a vinylor fiberglass frame, or wood frame clad withaluminum or vinyl to be consistent with U.S.Air Force standards for new construction. Thelow-E coating must have an emissivity valueless than 0.40.

Enter the type of window already installedand the type to be installed during revitalizationon Form G.17. To determine the heating andcooling savings from the new windows, performthe following steps using Figs. 4.19 and 4.20and Form G.8.

1. Annual space-heating energy savings per

square foot of window area for varioustypes of windows (compared with asingle-glazed window with a metal frame)are provided in Fig. 4.19. The annualheating savings per square foot of windowarea is obtained from Fig. 4.19 using theheating-degree days for the installation.

Calculate the heating savings of the newwindow by subtracting the savings of theexisting window from those for the newwindow.

2. The annual space-cooling electricity savingsper square foot of window area is obtainedfrom Fig. 4.20 using the cooling-degreedays for the installation. Determine thecooling savings of the new window in themanner described in step 1.

3. Calculate the total annual energy savings bymultiplying the combined space-heating andspace-cooling savings (after convertingspace-cooling savings from kWh to MBtuby multiplying by 0.003413) by the newwindow area to be installed. Enter the totalannual energy savings on Form G.17.

STORM WINDOWS

Although the popularity of storm windowshas declined as primary windows haveimproved, storm windows still provide arelatively inexpensive means to improve theenergy efficiency of single-glazed windows andreduce condensation and icing problems. Likeprimary windows, storm windows tend to wearout over time. Storm windows that are no longerfunctional (poorly fitting or damaged) should bereplaced automatically.

Unlike prime windows, storm windows areeasy to install. It takes no more than half anhour to install a storm window, and generally ahigh-quality storm window costs less than 25%of the cost of a new energy-efficient window.Therefore, it may be economical to install stormwindows on existing single-glazed windowswhen it is not economical to replace them withnew windows.

The cost-effectiveness of installing stormwindows can be determined by using Fig. 4.21and Form G.9.

1. Figure 4.21 provides the annual space-heating

energy savings per square foot of windowarea for storm windows installed onsingle-glazed windows with metal frames(with no thermal break) and single-glazed


Fig. 4.19. Annual space-heating energy savings per square foot of window area from installinghigher-efficiency windows compared with a single-glazed window with a metal frame. Savings are for windowsthat are (a) double-glazed with a metal frame or single-glazed with a nonmetallic frame; (b) double-glazed with athermally broken metal frame; (c) triple-glazed with a thermally broken metal frame, double-glazed with a nonmetallicframe, or double-glazed with a thermally broken metal frame and low-E coating; and (d) triple-glazed with anonmetallic frame or double-glazed with a nonmetallic frame and low-E coating.

Fig. 4.20. Annual space-cooling electricity savings per square foot of window area from installinghigher-efficiency windows compared with a single-glazed window with a metal frame. Savings are for windowswith nonmetallic frames or metal frames with a thermal break and that are (a) double-glazed, (b) triple-glazed, and(c) double-glazed with a low-E coating.


windows with nonmetallic frames or thosewith thermal breaks.

2. The annual space-cooling energy savings persquare foot of window area is obtained fromcurve (a) of Fig. 4.20.

3. The annual cost savings of the heating andcooling energy savings is calculated inForm G.9 using the installation’s costs forfuel, and the present value of the energysavings is calculated using a 25-year presentworth factor.

4. The A/E must estimate the total cost topurchase and install the storm window persquare foot of window area.

5. The storm window meets militarycost-effective criteria if the SIR is greaterthan or equal to 1.25 and the SPP is lessthan or equal to 10. Note the presence of a storm window on

Form G.17, as well as whether a storm windowwill be installed during revitalization. Calculatethe annual space-heating energy savings bymultiplying the savings obtained from step 1 bythe window area to receive storm windows.Enter this savings on Form G.17.

Fig. 4.21. Annual space-heating energy savings per square foot of window area from installing stormwindows on single-glazed windows with ( a) metal frames without a thermal break and ( b) nonmetallic framesand metal frames with a thermal break.


4.2.9 Doors

OPAQUE EXTERIOR DOORS

It is not cost effective to replace existingopaque exterior doors that are in adequatecondition on the basis of potential energysavings. However, weather stripping andthresholds should be replaced if they aredetermined to be worn or near the end of theirservice life during the site inspections.

When revitalization requires replacing theexterior doors, a U.S. Air Force standard1 3/4-in.-thick insulated metal door with athermal break or a solid-core wood door willprovide satisfactory thermal performance.Ensure that all replacement doors are thoroughlyweather-stripped and have an appropriatethreshold to reduce infiltration.

Screen and self-storing storm doors arerequired on all exterior hinged doors. Anexisting storm door in adequate condition(including weather stripping) may be retained.Replace storm doors in deficient condition with

new storm doors conforming to current militaryservice standards for new construction.

GLASS EXTERIOR DOORS

New or replacement glass exterior doors(sliding or French) must be warranted forarchitectural reasons similar to those discussedfor windows. As with windows, specify adouble-glazed glass door with low-E glass, witheither a vinyl or fiberglass frame or wood frameclad with aluminum or vinyl, when a new glassexterior door is needed.

Enter the type of glass exterior door alreadyinstalled in the housing unit and the type to beinstalled during revitalization on Form G.17.Determine the total annual energy savings usingForm G.10 and the same procedure discussed inSect. 4.2.8, “Windows.”

Replace weather stripping if it is worn ornear the end of its service life in all cases.


4.2.10 Heating and Cooling EquipmentReplacement Options

Space-heating and space-cooling equipmentmay be replaced as part of revitalization becauseresulting energy savings can be obtained costeffectively or because replacement is needed forreasons not related to energy. The first step is todetermine the types of equipment mostappropriate for the installation and housing unit,although replacement systems will generally beof the same type and use the same fuel as theoriginal equipment.

There are no restrictions on the use of gas-and oil-fired furnaces and boilers.

Air conditioning is provided primarily bycentral-type systems, although evaporativecoolers are used. For Air Force bases, airconditioning is restricted to locations whereambient temperatures during the six warmestmonths are greater than one of the following: • 67°F wet-bulb for more than 800 hours,• 80°F dry-bulb for more than 350 hours, or• 93°F dry-bulb for more than 155 hours.

Air Force guidelines prohibit the use of air

conditioning in Maine, Vermont, NewHampshire, and Alaska but allow its use at somebases in all remaining states (see Fig. 4.22). Thenecessity for air conditioning should not beassumed if these guidelines are met. Rather, inborderline locations (especially installations inthe northernmost and westernmost states),mechanical or natural ventilation should beprovided when analysis shows that comfort canbe maintained without air conditioning.

Design considerations should be carefullyreviewed to eliminate the need for mechanicalair conditioning wherever possible, especially inborderline locations. Design considerationsinclude locating carports on southwest and westsides of units, reducing the window area on westand southwest exposures, using reflective ortinted glazings if they are cost effective, using

trees and plantings, and using shading devices.Orientation considerations are difficult toimplement because generic housing types atinstallations face random directions, souniversal designs cannot be developed. Attics ofhousing units with air conditioners should beventilated adequately. Ventilation guidelines areprovided in Chapter 2 of the 1993 ASHRAEHandbook—Fundamentals.

Use of heat pumps is restricted to locationswith heating design temperatures (97.5% basis)greater than 12°F and with less than 5000heating-degree days. Heat pumps are generallyapplicable in all southern states (except in somehigh-altitude locations) and can be used inselected parts of some western and eastern statesas indicated in Fig. 4.18; heat pump use isprohibited in most northern states.

Ground-source heat pumps are gainingpopularity as efficient space-conditioningsystems, but they remain a relatively newtechnology and have not yet received extensiveapplication. Therefore, ground-source heatpumps are not addressed in this guide andshould not be installed unless part of atechnology demonstration program.

Electric resistance space heating (exceptsupplemental heating required for heat pumps)should be avoided except where specialcircumstances dictate.

Conversion to alternate fuels should beseriously considered to reduce heating costs andto standardize the type of fuel used for spaceheating and for other purposes in the house andat the installation. This decision must be basedon life-cycle cost analysis and must be made atthe base rather than the house level because ofthe variety of issues involved, such as utilityinfrastructure and environmental concerns.Switching from electricity or oil to natural gas isgenerally the more common conversion.


Fig. 4.22. Air Force guidelines on use of air conditioning.


4.2.11 Heating and Cooling EquipmentReplacement Selection

Space-heating and space-cooling equipmentwill be replaced automatically as part ofrevitalization under the following conditions:

• replacement is dictated by the military,• the equipment is nonoperational,• replacement is required for health and safety

reasons,• a new fuel source is to be used for space

heating,• replacement is needed to implement an

improved system design,• the equipment is in such condition that it

cannot provide useful service for 2 moreyears, or

• the equipment is older than the followingmedian service lives:— 15 years for central air conditioners,— 15 years for heat pumps,— 18 years for gas- or oil-fired furnaces,

and— 25 years for gas- or oil-fired boilers.

FURNACE OR BOILER

A new gas- or oil-fired furnace or boilermust have an AFUE rating of 80%. Specify ahigh-efficiency (greater than 90% AFUE) gas-or oil-fired furnace or boiler rather than aminimum-efficiency unit if the incrementalinvestment is cost effective as determined usingFig. 4.23 and Form G.11.

1. The annual space-heating energy savings per

square foot of floor area of the housing unitfor a high-efficiency unit compared with an80% AFUE unit is obtained from Fig. 4.23using the heating-degree days for theinstallation and the type of housing unitbeing considered: detached unit, individualunit of a duplex, or individual unit of a

townhouse-type building (one or twocommon walls).

2. The annual cost savings for a high-efficiencyfurnace or boiler is calculated in Form G.11by multiplying the annual energy savings bythe floor area of the unit and theinstallation’s cost for natural gas or oil. Thepresent value of the cost savings iscalculated by multiplying the cost savingsby an 18-year present worth factor.

3. The A/E must determine the incremental costof installing the high-efficiency unitcompared with the 80% AFUE unit. Theincremental cost includes the greatermaterial costs for the higher-efficiency unit,as well as other considerations such asgreater installation labor and the need for anew flue (assuming the 80% AFUE unitwould not itself need a new flue or chimneyliner).

4. The high-efficiency unit meets militarycost-effective criteria compared with the80% unit if the SIR is greater than or equalto 1.25 and the SPP is less than or equalto 10. Enter on Form G.17 the AFUE of the

furnace or boiler already installed in the housingunit (see Table 4.3 to estimate a value) and ofthe system to be installed during revitalization.The heating savings obtained from replacing theold system with the new furnace or boiler is notthe value obtained from step 1 because only theincremental savings from an 80% to ahigh-efficiency unit was considered. Rather,estimate the heating savings as outlined inSect. 4.2.12 for furnaces or boilers. Multiplythis savings by the total floor area of thehousing unit and enter this value on Form G.17.


Fig. 4.23. Annual space-heating fuel savings per square foot of living area for high-efficiency furnacesand boilers (>90% AFUE) compared with minimum-efficiency units (80% AFUE).

Table 4.3. Annual fuel utilization efficiency (%)

Steady-stateefficiency (%)

Type 1a Type IIb Type IIIc Type IVd

65 59 56 52 49

70 63 60 56 53

72 65 62 58 55

75 68 65 60 57

80 72 69 64 61

82 74 71 66 62

85 77 74 68 65

90 82 78 72 68

aType I: Oil-fired furnace/boiler. Gas-fired furnace/boiler with vent damper and intermittent ignition device. bType II: Gas-fired furnace/boiler with vent damper and pilot light. Gas-fired furnace/boiler without a vent damper

and pilot light installed outside. cType III: Gas-fired furnace/boiler with an intermittent ignition device and no vent damper. dType IV: Gas-fired furnace/boiler with pilot light and no vent damper.


AIR CONDITIONER

A new air conditioner must have a seasonalenergy efficiency ratio (SEER) rating of not lessthan 10.0 to meet the requirements of theNational Appliance Energy Conservation Act of1987. This act supersedes U.S. Air Forcerequirements setting the minimum SEER tovalues less than 10.0. A high-efficiency(12-SEER) air conditioner should be specifiedrather than a minimum-efficiency unit if theincremental investment meets militarycost-effective criteria as determined usingFig. 4.24 and Form G.11 following theprocedure outlined for furnaces and boilers andusing a 15-year present worth factor.

The annual electricity savings per squarefoot of floor area of the housing unit for a12-SEER unit compared with a 10-SEER unit isobtained from Fig. 4.24 using thecooling-degree days for the installation and thetype of housing unit being considered: detachedunit or individual unit of a duplex or

townhouse-type building (one or two commonwalls).

Enter on Form G.17 the SEER of the airconditioner already installed in the housing unit(see Table 4.4 to estimate a value) and of theone to be installed during revitalization. Thecooling savings obtained from replacing the oldsystem with the new air conditioner is not thevalue obtained from following the procedurejust discussed because only the incrementalsavings from a 10- to a 12-SEER unit wasconsidered. Rather, estimate the cooling savingsas outlined in Sect. 4.2.12 for air conditioners.Multiply this savings by the total floor area ofthe housing unit, convert kWh to MBtu bymultiplying by 0.003413, and enter this value onForm G.17.

HEAT PUMP

A new heat pump must have a SEER ratingof not less than 10.0 and a heating seasonalperformance factor (HSPF) of not less than 6.8to meet requirements of the National Appliance

Fig. 4.24. Annual space-cooling electricity savings per square foot of living area of high-efficiency airconditioners and heat pumps (12 SEER) compared with minimum-efficiency units (10 SEER).


Energy Conservation Act of 1987. This actsupersedes U.S. Air Force requirements settingthe minimum SEER and HSPF to lower values.Specify a high-efficiency (12-SEER and7.5-HSPF) heat pump rather than aminimum-efficiency unit if the incrementalinvestment meets military cost-effective criteriaas determined from using Figs. 4.24 and 4.25,Form G.11, a 15-year present worth factor, andthe procedure outlined for furnaces or boilerspreviously in this section.

The total electricity savings of ahigh-efficiency heat pump is the sum of theelectricity savings for air conditioning(Fig. 4.24) and heating (Fig. 4.25). The annualcooling savings for a 12-SEER heat pumpcompared with a 10-SEER unit is obtained fromFig. 4.24 in the same manner as described for anair conditioner. The annual heating savings for a7.5-HSPF unit compared with a 6.8-HSPF unitis obtained from Fig. 4.25 using the

heating-degree days for the installation and thetype of housing unit being considered: detachedunit, individual unit of a duplex, or individualunit of a townhouse-type building (one or twocommon walls).

Enter on Form G.17 the SEER and HSPF ofthe heat pump already installed in the housingunit (see Table 4.4 to estimate values) and of theone to be installed during revitalization. Theheating and cooling savings obtained fromreplacing the old system with the new heatpump is not the value obtained from followingthe procedure just described because only theincremental savings from a 10- to 12-SEER and6.7- to 7.5-HSPF unit was considered. Rather,estimate the heating and cooling savings asoutlined in Sect. 4.2.12 for heat pumps.Multiply these savings by the total floor area ofthe housing unit, convert kWh to MBtu bymultiplying by 0.003413, and enter the sum ofthese values on Form G.17.

Table 4.4. Air conditioner and heat pump efficiencies

Year air conditioner or heat pump was built SEER HSPF

1976 7 5.5

1982 8 6.0

1988 9 6.3

1992 10 6.8


Fig. 4.25. Annual space-heating electricity savings per square foot of living area of high-efficiency heatpumps (7.5 HSPF) compared with minimum-efficiency units (6.8 HSPF).


Fig. 4.26. Annual space-heating fuel savings per square foot of living area from replacing an existingfurnace or boiler with an 80% or 92% AFUE unit.

Fig. 4.27. Annual space-cooling electricity savings per square foot of living area from replacing anexisting air conditioner or heat pump with a higher-efficiency unit (10 or 12 SEER).


estimated from step 1 by the total floor area ofthe housing unit, convert kWh to MBtu bymultiplying by 0.003413, and enter this value onForm G.17.

HEAT PUMP

Replace the existing heat pump with ahigher-efficiency unit (10-SEER and 6.8 HSPF,or 12-SEER and 7.5 HSPF) if the investmentmeets military cost-effective criteria asdetermined using Figs. 4.27 and 4.28,Form G.12, and the procedure outlined earlierfor replacement furnaces and boilers. The totalelectricity savings of a higher-efficiency heatpump is the sum of the savings for airconditioning (Fig. 4.27) and heating (Fig. 4.28).Obtain the annual cooling savings per squarefoot of floor area of the housing unit for the 10-and 12-SEER units from Fig. 4.27 using the

cooling-degree days for the installation and theSEER of the existing system. Obtain the annualspace-heating savings per square foot of floorarea of the housing unit for the 6.8- and7.5-HSPF units from Fig. 4.28 using theheating-degree days for the installation and theHSPF of the existing system. The efficiencies ofthe existing system can be estimated fromTable 4.4 using the age of the unit. Use a15-year present worth factor in the calculations.

Enter on Form G.17 the SEER and HSPF ofthe heat pump already installed in the housingunit and of the one to be installed duringrevitalization. Multiply the heating and coolingsavings obtained from step 1 by the total floorarea of the housing unit, convert kWh to MBtuby multiplying by 0.003413, and enter the sumof these values on Form G.17.

Fig. 4.28. Annual space-heating electricity savings per square foot of living area from replacing anexisting heat pump with a higher-efficiency unit (6.8 or 7.5 HSPF).


4.2.13 Heating and Cooling EquipmentSizing and Location

New and replacement equipment must beproperly sized; oversizing, particularly, must beavoided. Equipment capacity must be matchedto the design heating and cooling loads of thehousing units, which are calculated assumingpost-revitalization conditions (e.g., insulationlevels and system efficiencies). Calculate designheating and cooling loads, and select equipmentsizes using either (a) the procedure outlined inChapter 25 and basic data in Chapters 22through 28 of the 1993 ASHRAEHandbook—Fundamentals, (b) proceduresdescribed in ASHRAE’s Cooling and HeatingLoad Calculation Manual (GRP 158),(c) Air-Conditioning Contractors of AmericaResidential Load Calculation (Manual J), or(d) other approved calculation procedures. Acopy of these calculations shall be provided tothe program manager for review and approval.

The floor plan and construction details mustbe known to calculate heating and cooling loads.Wall, ceiling, and floor construction and typeand thickness of insulation are needed, as arewindow and external door characteristics.

To perform heating load calculations, use aninterior temperature of 68°F. Use a 78°F interiortemperature to perform cooling loadcalculations.

New equipment should be smaller thanexisting units unless particular circumstances(such as a significantly increased heated orcooled area) warrant larger equipment.

The A/E must identify proper locations forthe outdoor units of new and replacement airconditioners and heat pumps within the contextof the overall revitalization design, rather thanleaving such decisions to the discretion of thecontractors. Outdoor units must be located awayfrom shrubs, decks, and other objects that canrestrict airflow or promote recirculation. Plantsaround outdoor units should be types that do notrelease significant pollen or leaves that can plugheat exchanger surfaces. A clear area of at least2 ft surrounding the outdoor unit isrecommended. Outdoor units should also belocated away from clothes dryer exhaustbecause lint can plug the heat exchanger coiland chlorine residue from the dryer exhaust candestroy it.


4.2.14 Other Heating and CoolingEquipment Retrofits

A number of retrofits to space-heating andspace-cooling equipment should be consideredif current systems are not replaced.

INTERMITTENT IGNITION DEVICE

Investigate the cost-effectiveness ofintermittent ignition devices (IIDs) for gas-firedfurnaces and boilers (not oil-fired or electricsystems) if the existing space-heating systemshave pilot lights and the pilots remain lit allyear. Their cost-effectiveness can be determinedusing Fig. 4.29, Form G.13, and the procedureoutlined for replacement furnaces and boilers.The annual energy savings is obtained fromFig. 4.29 using the heating-degree days for theinstallation. Use an 18-year present worth factorin the calculations.

Note the presence of an IID on Form G.17,as well as whether one will be installed duringrevitalization. Enter the annual heating savingsobtained from the energy savings calculationprocedure on Form G.17.

IIDs cannot always be installed. There maybe insufficient room to place the IID in theheating system cabinet, or there may beinsufficient space for the contractor to work,making installation time lengthy and thus costshigh.

VENT DAMPER

Investigate the cost-effectiveness of thermalvent dampers for gas-fired furnaces and boilers(not oil-fired or electric systems) if a ventdamper or gas power burner is not present.Cost-effectiveness can be determined using

Fig. 4.29. Annual space-heating fuel savings from installing an intermittent ignition device for a gas-firedfurnace or boiler with a pilot light that remains lit all year.


Fig. 4.30, Form G.13, and the procedureoutlined for replacement furnaces and boilers.The annual energy savings is obtained fromFig. 4.30 using the heating-degree days for theinstallation and indicating whether the heatingsystem is installed in an intentionally orunintentionally heated space. An intentionallyheated (also called conditioned) space is onewith equipment and/or distribution systemoutlets designed to maintain a desiredtemperature in the space. An unintentionallyheated space (typically a basement) is one that isheated primarily from equipment jacket and/ordistribution system losses (there is little controlover the resulting temperature). Use an 18-yearpresent worth factor in the calculations. Ingeneral, thermal vent dampers will not beeconomical if the heating systems are located inunintentionally heated spaces.

Investigate the cost-effectiveness of anelectric vent damper for a furnace or boiler (gas-or oil-fired) if a damper, gas power burner, orflame-retention head burner is not present. For agas-fired system, an IID must be present or bespecified for installation as part of therevitalization. The cost-effectiveness of anelectric vent damper can be determined usingFig. 4.31, Form G.13, and the procedureoutlined for replacement furnaces and boilers.The annual energy savings is obtained fromFig. 4.31 using the heating-degree days for theinstallation and indicating whether the heatingsystem is installed in an intentionally orunintentionally heated space. Use an 18-yearpresent worth factor in the calculations.

If both a thermal and electric vent dampermeet the military cost-effective criteria, thenselect the damper with the highest NPV.

Note the presence of a vent damper onForm G.17, as well as whether one will beinstalled as part of revitalization. Enter theannual heating savings obtained from thesavings calculation procedure on Form G.17.

Specify vent dampers on water heaters if thewater heater and furnace or boiler are vented

through a common flue and a vent damper isbeing specified for the furnace or boiler.

FLAME-RETENTION HEAD BURNER

Specify flame-retention head burners onoil-fired furnaces and boilers that haveconventional-type burners and that haveexpected lifetimes of more than five years.When a flame retention head burner is installed,lower the firing rate of the system by reducingthe nozzle at least one size and install a ceramicfiber liner (wet pack) in the combustionchamber to tolerate higher flame temperatures.

TUNE-UPS

Specify a tune-up on all space-heating andspace-cooling systems that are not beingreplaced to bring them to peak operatingefficiency and to correct any health and safetyproblems. Tasks to be performed under suchtune-ups are identified in Sect. 5.5, “HVACEquipment.”

CONTROLS

Specify new thermostat control systemswhen current systems are not operational andwhen new heating and cooling systems arebeing installed. Setback-type controls arerequired, and controls with automaticswitchover between heating and cooling are notallowed.

Locate a new thermostat in a centrallocation within the housing unit (where thetemperature is representative of the primaryliving area of the unit) and on an interior wall.Do not locate it where sun can strike thethermostat or the wall, on an uninsulatedexterior wall, or on a wall (interior or exterior)with an air passage behind it (i.e., with a cavitythat permits air transfer to the attic orbasement/crawl space).


Fig. 4.30. Annual space-heating fuel savings from installing a thermal vent damper on a gas-fired furnaceor boiler installed in an intentionally or unintentionally heated space.

Fig. 4.31. Annual space-heating fuel savings from installing an electric vent damper on a furnace orboiler installed in an intentionally or unintentionally heated space.


4.2.15 Air Distribution System

There are three options for revitalizing theair distribution system:

• replace the existing system,• modify the existing system, or• repair the existing system.

Visual inspections performed by the A/E

and results of the blower-door inspectionperformed by a qualified inspector will indicatewhich of these three options, if any, should bespecified. In all cases, new ductwork and repairsto existing ducts shall be performed accordingto procedures outlined in Sect. 5.6, “AirDistribution System Repair and ConstructionSpecifications.”

REPLACE THE EXISTING SYSTEM

Extensive modification of the interior of thehousing unit can require a major reconfigurationof the distribution system. In that case,installation of a new system is likely to be lessexpensive than adapting the existing system.

System replacement is also likely to bemore cost effective than repair for systems withextensive damage or deterioration to joints andductwork. This situation typically applies todistribution systems with the followingcharacteristics:

• round metal supply ducts with damaged

circumferential joints and/or joints with nosealant and no mechanical support,

• ductboard systems with damaged or leakingjoints, and

• flexduct systems with loose or damagedjoints. However, rectangular metal ducts with

lapped circumferential joints that are notdamaged should be retained and used whenpossible.

New air distribution systems must meet aprescriptive air-leakage performance criteria.The air-leakage of new ductwork systemsfollowing revitalization must be less than150 cfm when the ductwork is pressurized to50 Pa.

Compliance with this criteria shall beverified through performance testing of arandomly selected sample of housing units. Acompliance testing procedure is provided inSect. 5.7, “Air Distribution System PerformanceTesting,” and shall be specified in the designpackage. This procedure relies on themeasurement procedure specified inAppendix E. The installation procedures fornew ductwork outlined in Sect. 5.6, “AirDistribution System Repair and ConstructionSpecifications,” shall be specified. In addition,common duct problems as described inAppendix F must be avoided in the design.Techniques needed to repair and seal ducts asdescribed in Sect. 5.6 will be needed and shouldalso be conveyed in the design package.

To document the duct air-leakage analysis,enter the initial leakage rate of the existingdistribution system on Form G.17, and enter theterm “new system” in the column entitled“Revitalized unit.” If a measured value from theduct air-leakage inspection is not available,assume a current leakage rate of 150 cfm50 foran existing system in good condition asobserved during the field inspection, 250 cfm50if some leaks are visible, and 350 cfm50 if thesystem is totally deteriorated (many visibleleaks). For the purposes of completingForm G.17, estimate the potential energysavings for this measure as follows:

1. Determine the percentage of energy savings

from Fig. 4.32 using the initial leakage rateof the distribution system and using thecurve for a new ductwork system.

2. Estimate the current heating and coolingenergy consumption of the housing unit by


subtracting 25 MBtu/ft2 from the currenttotal energy consumption intensity (seeSect. 4.2.20 and Sect. 4.1.1) and multiplythis difference by the existing intentionallyconditioned area (Form G.17). If the totalenergy consumption intensity cannot beaccurately estimated from availableinstallation data, then estimate the currentheating and cooling energy consumption byadding the heating and cooling portions ofthe CAPS energy budget (see Sect. 4.1.1and Sect. 3.2) and multiplying this sum bythe existing intentionally conditioned area.

3. Multiply the current heating and coolingenergy consumption calculated in step 2 bythe percentage energy savings from step 1.Enter this value on Form G.17.

MODIFY THE EXISTING SYSTEM

When portions of a duct system areinaccessible for repair, consider replacement ofthe inaccessible ducts with new ductwork and

repair of the remaining ducts. The following areexamples of this situation:

• deteriorated return ducts fabricated from

drywall and building framing, and• stud bay cavities and floor joist cavities

used as return ducts. This option may also be required when

replacement of the heating and coolingequipment or modifications to the living spacerequire rerouting or extension of the distributionsystem. For example, installing a new gas-firedfurnace in a new location may requireinstallation of new supply and return mainducts. To minimize costs, use parts of theexisting system if they are structurally sound. Inparticular, retain rectangular metal ducts withundamaged lapped circumferential joints, anduse them for such modifications when possible.

The installation procedures for newductwork outlined in Sect. 5.6, “Air DistributionSystem Repair and ConstructionSpecifications,” shall be followed. In addition,

Fig. 4.32. Potential percentage energy savings from installing a new air distribution system andmodifying or repairing the existing system.


common duct problems as described inAppendix F must be avoided in the design.Techniques needed to repair and seal ducts asdescribed in Sect. 5.6 will be needed and shouldalso be conveyed in the design package.

Portions of the air distribution system thatwill be retained during revitalization must havethe major air-leakage deficiencies identified bythe duct inspection repaired and sealed. Repairspecifications for duct air-leakage reductionoptions are provided in Sect. 5.6, “AirDistribution System Repair and ConstructionSpecifications.”

To document the duct air-leakage analysis,enter the initial leakage rate of the distributionsystem on Form G.17 for the existing unit, andenter the term “modified system” in the columnentitled “Revitalized unit” if this option isselected. Enter a leakage rate of 250 cfm50 if ameasured value from the blower-door inspectionis not available. The potential energy savings forthis measure can be calculated using Fig. 4.32,the curve for a modified system, and theprocedure outlined earlier for replacing theexisting system.

REPAIR THE EXISTING SYSTEM

Consider repairing the existing system whenany of the following is true:

• damage or deterioration is limited so thatrepairs are more cost effective thanreplacing existing ducts,

• repairs can be made to accessible ducts withleaking joints, or

• modifications to the distribution system arenot required for space or equipmentmodifications. Housing units in which a significant portion

of the air distribution system will be retainedduring revitalization must have the majorair-leakage deficiencies identified by the ductinspection repaired and sealed. Repairspecifications for duct air-leakage reductionoptions are provided in Sect. 5.6, “AirDistribution System Repair and ConstructionSpecifications.”

To document the duct air-leakage analysis,enter the initial leakage rate of the distributionsystem on Form G.17 for the existing unit, andenter the term “repaired system” in the columnentitled “Revitalized unit.” Enter a leakage rateof 250 cfm50 if a measured value from theblower-door inspection is not available. Thepotential energy savings for this measure can becalculated using Fig. 4.32, the curve for arepaired system, and the procedure outlinedearlier for replacing the entire system.


4.2.16 Domestic Water Heating System

WATER HEATER REPLACEMENTSELECTION

The existing water heater may need to bereplaced because its condition makes itnecessary or because the revitalization projectrequires that the water heater be relocated. Awater heater should also be replaced if its age isat or above the unit life expectancy (seeTable 4.5). New oil-fired water heaters shouldnot be installed. Most Air Force bases areconverting oil-fired space- and water-heatingsystems to natural gas as part of a facilitiesimprovement program. Residential heat pumpwater heaters are generally not economical and,thus, should not be installed.

When the water heater will be replaced aspart of the revitalization project, perform thefollowing analyses.

Determine the Most Cost-EffectiveFuel

When natural gas is available at the street orin the house, use Fig. 4.33 to determine whethergas or electricity is more cost effective. Enterthe figure with the actual fuel costs for theinstallation. If the intersection of the gas andelectricity costs falls above the line in the figure,

gas is more cost effective. If the intersection isbelow the line, electricity is more cost effective.

If the existing unit already uses the mostcost-effective fuel, skip the conversion analysisand proceed with the selection of the efficiencylevel.

Determine the Cost-Effectiveness ofFuel Conversion

The cost-effectiveness of fuel conversion isdetermined using Figs. 4.34 and 4.35 andForm G.14 and is based on comparing aminimum-efficiency electric heater with aminimum-efficiency gas heater. The minimumefficiency for a water heater is dependent on itssize and fuel type (see Table 4.5).

Use Fig. 4.34 to find the annual energy costfor a gas water heater, and use Fig. 4.35 todetermine the annual cost for an electric waterheater. Use the lines for minimum-efficiencywater heaters in both cases. Enter these costs inForm G.14 as the “cost-effective fuel” and the“other fuel” depending on the cost-effective fuelanalysis performed previously. Calculate theannual energy cost savings by subtracting thecost for the “cost-effective fuel” from the costfor the “other fuel.”

Table 4.5. Characteristics of water heaters

TypeMinimum energy factora

30-gal tank 40-gal tank 50-gal tank Life expectancy

Gas 0.56 0.54 0.53 8–12 years

Electric 0.89 0.88 0.86 10–15 years

Oil 0.53 0.51 0.50 8–12 years

aAn energy factor is a measure of the overall efficiency of a water heater. It compares theenergy supplied in heated water with that consumed by the water heater. The following equationshave been set by the Department of Energy to determine these levels: Gas: 0.62–0.0019 ⋅ volume(gal); Oil: 0.59–0.0019 ⋅ volume (gal); Electric: 0.93–0.00132 ⋅ volume (gal).


Fig. 4.33. Fuel selection for domestic water heating.

Fig. 4.34. Annual energy consumption—gas (and oil) hot water system.


The present values of the energy costs arecalculated in Form G.14 using a 12-year presentworth factor. Subtract the present value of theenergy cost for the system using thecost-effective fuel type identified previously(typically gas) from the present value of theother system (typically electricity) to obtain thepresent value of the energy savings fromconversion.

The A/E must determine the total costs ofconversion. For converting from electricity togas, these costs include flue installation, the gashookup (possibly including the service entrancepiping and piping to the water heater), and theincremental cost (if any) of aminimum-efficiency gas unit above aminimum-efficiency electric replacement unit.Similar costs would occur in converting fromgas to electricity.

Conversion meets military cost-effectivecriteria if the SIR is greater than or equal to 1.25and the SPP is less than or equal to 10.

Select the Highest-Efficiency,Cost-Effective Water Heater

Determine whether to use aminimum-efficiency or a higher-efficiencywater heater by using Fig. 4.34 (natural gas) or4.35 (electric), together with Form G.15.

Determine the cost-effectiveness of theunits by comparing the high-efficiency unit withthe minimum-efficiency unit. The minimumefficiency for a water heater is dependent on itssize and fuel type (see Table 4.5). Efficienciesof high-efficiency units can be as high as 0.70for units fueled with oil and gas and 0.97 forelectric units.

Use Fig. 4.34 or 4.35 to find the annualenergy costs for a minimum- and high-efficiency water heater. The cost savings of thehigh-efficiency water heater is the differencebetween the energy costs. More than onehigh-efficiency water heater (e.g., a 91%- and a97%-efficient electric water heater) may betested in this manner.

Fig. 4.35. Annual energy consumption—electric hot water system.


The present value of the cost savings iscalculated in Form G.15 using a 12-year presentworth factor.

Water heater efficiencies other than thoseshown in the figures may be available.Interpolate between the figure lines toapproximate their annual fuel costs.

The A/E must determine the incrementalcost of the high-efficiency water heatercompared to the minimum-efficiency unit. Thehigh-efficiency unit meets militarycost-effective criteria if the SIR is greater thanor equal to 1.25 and the simple payback periodis less than or equal to 10.

WATER HEATER EQUIPMENTSELECTION

Evaluate existing fully adequate waterheaters that are not planned for replacement asto the potential to reduce operating coststhrough changing fuels and/or increasing theefficiency of the water heater. Follow thethree-step process just outlined. Determine thecost-effective fuel as in step 1. If the existingfuel is not the cost-effective choice, proceedwith step 2 to determine if conversion meets thecost-effective criteria. Complete step 3,regardless of the outcome of the fuel selectionevaluation, to determine if replacement with animproved-efficiency water heater meets thecost-effective criteria or to determine thecost-effective efficiency of the new water heaterresulting from fuel conversion. In steps 2 and 3,use the full cost of a replacement water heaterrather than just incremental costs betweencomparative units.

DOCUMENTATION AND OTHERCONSIDERATIONS

Enter the efficiency and fuel of the presentlyinstalled water heater and those of the unit to beinstalled during revitalization on Form G.17.Combine the energy savings obtained fromsteps 2 and 3, and enter this value on Form G.17.

If the decision is not to replace the existingwater heater, consider an insulation blanket orwrap around the water heater. These typicallyrange in R-value from 4 to 10 and would doublethe thermal resistance of the tank wall, therebyreducing standby energy losses. This measure isalways cost effective for water heaters installedoutside the conditioned space.

Implement the following energy-savingmeasures on all new and existing water heaters.

1. Insulate the hot water pipes 3 ft up from the

tank for both indoor and outdoor tanks.2. Install heat traps (devices that eliminate the

convective heat transfer in the pipes) toincrease the efficiency of water heaters. Ifthe model has vertical water pipeconnections, energy can be saved by placingheat traps on the inlet and outlet waterconnections.

3. Set water heaters to 130 to 135°F. Highertemperatures increase standby losses andcan be a scalding hazard, and lowertemperatures can promote the growth ofLegionella pneumophila bacteria.

4. In addition to the water heater, replaceplumbing fixtures to save water and theenergy needed to heat the water. All sinkfaucets should have aerators installed tolimit the flow rate to 2 gpm or less. Showerheads should be rated at 2.5 gpm or less.


4.2.17 Exhaust Systems and Appliances

EXHAUST SYSTEMS

Evaluate existing exhaust systems as to theircondition and adequacy to perform theirintended function. Replacements or newsystems must conform to applicable codes andstandards. Review the following items duringthe analysis phase to ensure that the systemshave a minimum adverse effect on the energyperformance of the housing unit.

1. Bathroom exhaust fans should be ducted to the

exterior of the housing unit, terminating in aweatherproof roof, eave, or wall jack with aone-way back-draft damper or draft-stop toprevent the entry of outside air when the fanis off.

2. Dryer-exhaust dampers are subject to lintbuildup and sticking open. If a replacementis needed, install a quality damper that willminimize lint buildup.

3. A range hood should be ducted to the exteriorof the unit. Install a one-way back-draftdamper or draft-stop to prevent entry ofoutside air.

4. Powered attic exhaust fans are notrecommended. Soffit vents with ridge ventsare recommended. Gable end vents or highthrough-the-roof vents are alternatives toridge vents. Ventilation areas shouldconform to guidelines provided in Chapter 2of the 1993 ASHRAE Handbook—Fundamentals.

5. Whole-house fans can contribute significantenergy savings if they preclude the additionof air conditioning to a house. Take carethat attic ventilation openings are adequateto handle the fan flow and that the fandampers seal tightly during periods ofnonuse. A housing unit that is centrally airconditioned should not have a whole-housefan because there is little incentive for theoccupant(s) to use it in lieu of the airconditioning system.

APPLIANCES

Replace major appliances such asrefrigerators, ranges, and dishwashers that arenear the end of their service lives withenergy-efficient models during the revitalizationproject. The expected service lives of theseappliances are

• refrigerators—15 years,• dishwashers—10 years, and• ranges—15 years.

When selecting energy-efficient appliances,

consider not only gross energy consumption butalso how well the unit fits the task. Appliancesmay come with features that allow the user theoption of using less energy when the task issmall and progressively more energy as the tasksize increases. Some of these features may bebuilt-in; others depend on the user to choose thebest cycle or energy-saving feature. Becauseoccupants of military family housing do not payutility bills, there may be limited incentive forthem to use energy-saving features. Therefore,built-in features should be the first choice forappliance energy conservation.

Choosing an appliance that offsets theenergy requirements of another appliance maybe a benefit as well. Dishwashers with waterheaters built in will allow the house water heaterto be set at a lower temperature, saving overallenergy.

A key element in the analysis of majorappliances is determining the mostcost-effective fuel for use in ranges. Figure 4.36indicates when it is cost effective to use electricand gas ranges in new construction, when it iscost effective to retain present electric and gasranges during revitalization, and when it is costeffective to replace an existing adequate electricrange with a new gas range.


Fig. 4.36. Fuel selection for cooking ranges.


4.2.18 Lighting

Choosing appropriate, energy-saving,cost-efficient lighting is the goal of this section.Each space has a different purpose and thereforedifferent lighting requirements. Energyefficiency and cost-effectiveness can beincreased if the lighting selected respondscorrectly to its purpose. Design options shouldalso consider how to maximize natural lighting(daylighting).

BACKGROUND

Appropriate lamp (bulb) selection is themost significant single factor in energy- andcost-efficient lighting design. A number ofcomparative features must be evaluated:

• efficiency,• color rendition index (CRI),• correlated color temperature (CCT),• expected life, and• initial cost.

Lamp efficiency is a measure of

light-producing ability per unit of electricalpower measured in lumens per watt (LPW).Lamps that require a ballast, such as fluorescentlamps, must include the power consumption ofthe ballast. Typical efficiencies are as follows:

• standard incandescent: 12–18 LPW,• halogen: 16–19 LPW,• fluorescent: 60–90 LPW,• compact fluorescent and mercury vapor:

30–60 LPW, and• metal halide or high-pressure sodium:

75–150 LPW. The CRI of a lamp is the measure of how

accurately the lamp represents the color of anobject relative to daylight. The highest CRI is100, which presents the color as if the objectwere viewed in daylight. A CRI above 80 isconsidered to indicate good quality. Standard

incandescent lamps typically have a CRI ofaround 95; the CRI of many fluorescent lamps ismuch lower, although some can providehigh-quality light.

The CCT of the lamp describes whether alamp has warm or cool tones. Warm tones(lower CCT values) are more often used inresidential applications because they tend to bemore flattering. Standard incandescent lampshave a CCT of 2,800.

In selecting a lamp type, note that smaller,brighter lamps can cause glare and shadows thatreduce the overall quality of the lighting designand reduce the satisfaction of the inhabitant withthe resulting lighting.

The difficulty of replacing bulbs is animportant factor in choosing lamp type. Fixturesin ceilings of staircases or outside can bedifficult to service. Fluorescent lamps have 5 to20 times the life of standard incandescent lamps,and halogen lamps last 3 to 4 times longer.

DAYLIGHTING

Consider natural lighting or daylightingtechniques in revitalization projects. Examplesinclude the following:

• removing a wall or portion of a wall to

allow the light from a window to penetrateinto a number of spaces,

• enlarging window areas to increase thetransmission of sunlight to many differentrooms, and

• installing skylights or clerestory windows(skylights with vertical glazing). If substantial renovations are required for

other purposes, daylighting techniques can beincorporated cost effectively. However, the useof some daylighting techniques can increase theenergy consumption of the house. For example,poorly positioned skylights or overly large


windows can increase both air conditioning andheating costs.

SELECTION OF NEW ORREPLACEMENT INDOOR FIXTURES

Except in limited-use areas such as attics,crawl spaces, and some storage spaces, all newinterior lighting must have an efficiency of atleast 30 LPW, a CCT less than 3500, and a CRIof at least 70. The CRI of compact fluorescentlamps must be at least 80. For fluorescent tubes,the efficiency must be at least 70 LPW.

Fluorescent lights are versatile and energyefficient. Use them in most spaces to provideboth task and general-purpose lighting. Useinexpensive fluorescent fixtures in general workspaces such as garages, basements, and storageareas. Use more expensive fluorescent fixtures,with higher-quality light (high CRI and lowCCT), for general lighting in bathrooms andkitchens. General bedroom lighting can also useeither ceiling or wall fluorescent fixtures. Allfluorescent fixtures must have electronic ratherthan magnetic ballasts.

Compact fluorescent replacement lamps arecost effective compared with incandescentlamps unless they are used infrequently. Thislimited use would occur in attics, crawl spaces,and some storage spaces. In other spaces,replacement fixtures (when needed) should befluorescent.

When replacement of fixtures is notwarranted by the condition of the existing

fixtures, evaluate replacement of theincandescent lamps with compact fluorescentlamps.

Halogen fixtures are appropriate for specifictask lighting or in areas where the light isdirected to a specific purpose. Halogen lampsare more efficient than regular incandescentlamps but not as efficient as fluorescent lamps.Because of their relative low cost, halogenlamps may be a better choice in locations wherelight use is infrequent and of short duration.

Table 4.6 lists recommended indoor lightingstrategies when lighting fixtures are beingreplaced during a revitalization project.Form G.16 is provided to assist in developing anappropriate lighting strategy for each individualtype of housing unit.

SELECTION OF NEW ORREPLACEMENT OUTDOORFIXTURES

Fluorescent fixtures can meet many outdoorlighting requirements efficiently. Specialprovisions are required for fluorescent fixturesused in harsh winter climates. Halogenincandescents with an infrared-reflectivecoating (HIR) or high-pressure sodium lampsare energy efficient, but energy savings may beoffset by their high initial cost. They are a goodchoice if long operation and general arealighting are required. All new exterior lightingmust have a CRI of 60 or greater and anefficiency of at least 30 LPW.


Table 4.6. Recommended lighting

Lighting fixture

RoomWall (W) orceiling (C)

Lamp type

Most efficient Efficient Control device

Living room N/A N/A N/A Switched outlets

Dining room C Hanging CF Chandelier H Dimmer on chandelier

Family room C Ceiling Fl Lamps CF 3-way switches

Hall C or W CF ceiling CF wall 3-way switches

Bath W FL1 CF Switch

Kitchen C & W FL CF Switch(es)

Utility room C FL CF Switch

Storage C or W FL CF Pull chain

Stairs C or W CF FL indirect wall 3-way switches

Hall upstairs C or W CF ceiling CF wall 3-way switches

BedroomsC and/or wall CF, hidden FL wall1 Lamps CF,

CF wallSwitch(es)

Basement,unfinished

C FL HSwitch(es) pull

chains

AtticC H I

Pull chainswitch

Outdoor W CF2 H Switch

Outdoor storageC H I

Pull chainswitch

GarageC CF2 H

Switchpull chain

FL = fluorescent, CF = compact fluorescent, H = halogen, I = incandescent.1T8 48 in. 32 watt.2If the temperature does not fall below 0°F and the lamp is enclosed by the light fixture, use a 20-watt screwbase

compact fluorescent with electronic ballast.


4.2.19 Site Improvements

LANDSCAPING

Landscape material can be used in two waysto reduce energy consumption for spaceconditioning in a dwelling: (1) to shade thestructure in the cooling season and (2) to reduceambient wind velocities around the structure inthe heating season.

Evaluate existing plant material noted in theinspection phase as to how it can contribute tothe overall landscape of the site. Retain mature,healthy trees and large shrubs that provide shadeto the south and west sides of the structure oradjacent pavement during the cooling season.Similarly, retain plant material, particularlyevergreens, located on the windward side(typically northwest, north, or northeast) of thestructure as it provides a wind break. Thisretention of plant material could require somemodification of otherwise standard site designsto accommodate this material.

Revitalization projects that include fundingfor installing additional landscape materialsshould develop designs that implement energyconservation opportunities as well as meetaesthetic and other landscape objectives.

The use of deciduous trees and shrubs toshade south and west facing walls, particularlythose that form the thermal envelope andcontain windows, is strongly recommended.Trees that shade the roof of residences canmarkedly reduce attic temperatures. However,energy benefits are less with attics that are wellinsulated (which is usually the case). In climateswhere solar gain in the winter is a benefit, usecare to select tree species without densestructures that cast significant shade even whennot in leaf. This shading would reduce thebenefits of solar gain in the heating season.

PAVEMENT

If practical, avoid significant amounts ofpavement (e.g., parking aprons and patios) onthe south and west sides of dwelling units withsignificant air conditioning requirements. Heatreflected from pavement within 10 ft of thestructure can markedly increase heat gainthrough the windows and walls of conditionedspace (if they are poorly insulated).

If it is impractical to remove or relocatepavement from these locations, attempt to shadethese areas with deciduous trees.


4.2.20 Documentation of Analysis Process

Documentation is a two-step process. Thefirst step summarizes the analysis process fromForms G.1–G.16 on Form G.17. The secondstep compares the performance of the revitalizedunit with an optimum newly constructed unit.Details of these steps follow.

ANALYSIS SUMMARY

Enter the installation name, housing unit ID,and intentionally conditioned floor area of theexisting unit on Form G.17. Also, enter theCAPS energy budget for an optimum, newlyconstructed unit of the same size, type, andlocation, as well as the estimated energyconsumption intensity calculated for the currentunit during the site inspection (see Sect. 4.1.1,“Energy Use Review”). The CAPS informationis provided in the project’s Request for Proposalor Statement of Work and is explained inSect. 3.2, “Selection of ECMs UsingCOSTSAFR.”

Summarize the impact of the individualcomponent analyses performed following theprocedures outlined in Sect. 4.2, “Analysis andSelection,” on Form G.17. This includesidentifying envelope and equipmentspecifications for the housing unit both as itcurrently exists and as it will exist afterrevitalization and entering the energy savingsfrom revitalization. Only the majorrevitalization activities that significantly affectenergy consumption or for which energysavings projections can be made are included onForm G.17. This form will provide an indicationof the impact of the cost-effectiveenergy-efficiency improvements achieved byrevitalization. Submit all forms to the programmanager for review and approval.

COSTSAFR COMPARISON

In addition to completion of Forms G.1 toG.17, the designer shall complete the six-pageCOSTSAFR analysis forms (see Chap. 3,“Design, Analysis, and Selection of Options forNew Housing,” for detailed methodology)provided in the project’s Statement of Workusing the options determined to be cost-effectivebased on the criteria contained in this chapter.This task will provide a comparison of theenergy performance of the revitalized unit tothat of an optimum, newly constructed unit ofthe same size, type, and location. Thiscomparison shall be submitted to the programmanager for review and approval.

The point system used in the COSTSAFRanalysis was developed to be applicable to newconstruction. It is unrealistic to expectrevitalization to achieve energy-efficiencylevels comparable in all cases to theCOSTSAFR minimum required point totalbecause of the limitations in dealing withexisting building structures. Efficiency levelsthat can be achieved cost effectively in buildinga new structure may not be achievable costeffectively in revitalization because of addedcosts to remove equipment, expose areas forinsulation, restore the building to finishedcondition, etc. An obvious example is wallinsulation, which is cost effective to installduring construction but may be prohibitivelyexpensive under revitalization because ofinterior and exterior wall characteristics.

Nevertheless, the A/E should ensure that allpossible energy-efficiency measures areconsidered and properly evaluated if theprojected point total of the revitalized unit isless than 75% of the minimum point total of acomparable “new” unit. A first step would be toensure that current efficiency levels and energydeficiencies were properly identified during thesite inspections.


5Chapter

SPECIFICATION OF SELECTEDENERGY-EFFICIENCY OPTIONS

5.1 Overview................................................................................... 5-15.2 Infiltration Repair Specification and Construction Tips.............. 5-25.3 Infiltration Performance Testing of Housing Units..................... 5-45.4 Windows and Doors.................................................................. 5-55.5 HVAC Equipment...................................................................... 5-75.6 Air Distribution System Repair and Construction

Specifications............................................................................ 5-115.7 Air Distribution System Performance Testing ........................... 5-16

5.1 Overview

This chapter provides the A/E with the textof specifications for use in revitalization andnew construction projects as a supplement tospecifications cited in the project’s Request forProposal or Statement of Work and applicable

military standards manuals identified inSect. 2.2, “Design, Analysis, and Selection ofOptions for New Housing,”and Sect. 2.3,“Design, Analysis, and Selection of Options forRevitalized Housing.”

SPECIFICATION OF SELECTED ENERGY-EFFICIENCY OPTIONS 5-1

5.2 Infiltration Repair Specifications andConstruction Tips

Use the following materials and proceduresto correct identified infiltration deficiencies inthe building envelope.

MATERIALS

Apply sealants after thoroughly removingmoisture, dust, dirt, oil, grease, or othersubstances which may diminish the bond of thesealant material.

Mastic and Fiberglass Tape (FiberglassMesh)

Mastic sealants are available in water-basedform for sealing penetrations and repairing holesin walls and ceilings. Water-based mastics arepreferable to petroleum-based mastics becauseof shorter curing times, easier cleanup, andmore “forgiving” application characteristics.When used with fiberglass tape, mastic can sealand provide strength to repairs of practically anyconfiguration. Mastic should generally beapplied over the entire joint between matedsurfaces and must not be diluted.

Mastic sealants shall conform to thefollowing safety requirements of UnderwritersLaboratory (UL) Standard 181, Class 1:

• a flame spread rating of less than 25 and• a smoke development rating of less than 50

in the dry, final state.

In addition, the mastic sealants shallconform to these characteristics:

• a solids content greater than 50% to reduceshrinkage on drying;

• the capability to adhere to manysurfaces—sheet metal, drywall, fiberboard,concrete, wood, and plastic; and

• a temperature range that includes thehighest and lowest temperatures likely to beencountered.

Urethane Foam

This material shall have the same safetyrequirements as mastic sealant and shall be ULrated.

Caulking

Long-lasting (20 years or more) siliconecaulking materials are required for sealing leaksin building envelopes. A treated variety must beused if the caulking will be painted. Thismaterial shall have the same safety requirementsas mastic sealant and shall be UL rated.

Blocking Materials

For large voids that cannot be sealed withfiberglass tape and mastic, rigid fiberglass orfiberboard of 0.5 in. or more in thickness shallbe cut to shape and sealed in the void space withmastic, urethane foam, or caulk. The followingalternative materials may be used whenapproved by the military inspector on theproject: corrugated cardboard, plywood, andplastic bags filled with fiberglass insulation.Large voids typically occur at electrical andplumbing penetrations and in attic bypassessuch as unblocked walls.

Flashing

Metal flashing cut to shape must be used toclose gaps around flues and chimneys to avoidplacing combustible material next to those hotsurfaces.

5-2 SPECIFICATION OF SELECTED ENERGY-EFFICIENCY OPTIONS

PROCEDURES

Seal penetrations, gaps between materials,and holes in walls using the materials describedpreviously and using the following procedures:

Penetrations

Use urethane foam for sealing aroundelectrical and plumbing penetrations because itexpands to fill the void totally as it cures. Masticand fiberglass tape may be used for thisapplication if urethane foam is unavailable. Usemetal flashing and fireplace mortar to sealaround flues and chimneys, as combustiblematerial must not be placed adjacent to thosehot surfaces.

Holes and Gaps in Walls and Ceilings

Mastic and fiberglass tape shall be used inmost cases to seal these types of leaks. Forlarger holes ( 2-in. diameter), use fiberboard tofill the hole or gap, and use mastic or caulk toseal around the filler.

Attic Bypasses and Voids AroundPlumbing Chases

These usually larger voids require afiberboard filler to be cut to fit the shape of thevoid. Seal these with mastic, caulk, or urethanefoam.

Sill Plate to Band Joist Seal

Apply urethane foam to fill all gaps andvoids between the sill plate and band joist.


5.3 Infiltration Performance Testing of Housing Units

BLOWER-DOOR TESTING

Randomly selected new and/or revitalizedhousing units shall be tested to determine thecompliance of the unit with the allowableair-leakage rate specified for the buildingenvelope. Units shall be selected by the programmanager. Testing shall be performed by a firmqualified to perform inspections using blowerdoors in accordance with procedures specifiedin Appendix C for building envelope testing.The testing firm shall be independent of theinstalling contractors or equipment suppliers forthis project. The specifications provided inAppendix B can be used to hire a qualified firm.

PERFORMANCE REQUIREMENTS

Building envelope air leakage shall begreater than or equal to (enter minimum valuedetermined from Sect. 4.2.6) but no more than(enter maximum value determined fromSect. 4.2.6) natural air changes per hour.

NUMBER OF TESTS REQUIRED

Infiltration testing shall initially beperformed on 10% of the housing units (e.g., 10of 100 housing units). If 90% of the tested unitspass the stated performance requirements (e.g.,nine of the ten tested units), no additionaltesting will be required. If less than 90% of theinitial sample pass (e.g., fewer than nine units),then the failed units shall receive correctiveaction and be retested, and an additional 10% ofthe housing units (e.g., ten additional units) shallbe tested. If 90% of the tested units pass (e.g.,

18 of the 20 tested units), no additional testingwill be required. This testing procedure shallcontinue in groups of 10% throughout the newand/or revitalized housing units until at least90% of the tested units comply with the statedperformance requirements.

Infiltration testing may be performed aftercompletion of all housing units beingconstructed or revitalized under the project.However, testing the building envelope on anongoing basis is recommended to avoidreplicating the same deficiencies in units yet tobe constructed or revitalized. In this case, forexample, a 100-housing-unit project could bedivided into five groups of 20 units. Testingwould be performed on 2 of the first 20 housingunits completed. If both units pass, no additionaltesting would be required for the first group of20 housing units. After the second group of20 housing units are completed, 2 of these20 units would be tested to determine if thesecond group of housing units passes. Testingby group would continue until all housing unitswere completed.

CORRECTION OF AIR-LEAKAGEDEFICIENCIES

The contractor shall supply all labor andmaterial required to make the leakage of alltested units conform to the stated performancerequirements. Units initially failing to meet thestated performance requirements shall beretested to verify their conformance aftercorrective actions have been accomplished.


5.4 Windows and Doors

Windows and glass exterior doors (doorswhose surface is 50% or more glazed) shallmeet the following standards and must becertified by an independent test laboratory.Windows that slide (double-hung, single-hung,and horizontal sliding) and glass exterior doorsshall meet the standards for “hung” windowsthat follow. Standards for casement windowsshall refer to all hinged or fixed windows.Jalousie windows, greenhouse windows, andother unspecified types of windows may not beused unless they are tested and conform to thestandards for hung windows.

Windows shall meet the following designpressure standards as designated by the NationalFenestration Rating Council:

• hung: DP25 (corresponds roughly to formerGrade 40), and

• casement: DP40 (corresponds roughly toformer Grade 60).

The following specific tests and minimumstandards are required to achieve these designpressure standards.• Operating force: The force necessary to

unlatch and open the window shall notexceed 30 lb for hung and 35 lb forcasement.

• Air infiltration: Using ASTM E 283,“Standard Test Method for Rate of AirLeakage Through Exterior Windows,Curtain Walls, and Doors,” the rate shall notexceed 0.25 cfm/ft2 for hung and0.15 cfm/ft2 for casement at a test pressureof 1.57 psf.

• Water penetration: Using ASTM E 547,“Standard Test Method for WaterPenetration of Exterior Windows, CurtainWalls, and Doors by Cyclic Static AirPressure Differential,” there shall be nowater penetration at 3.75 psf in three5-minute cycles with a 1-minute rest

between cycles for hung, and at 6.00 psf forcasement.

• Structural testing—Using ASTM E 330,“Standard Test Method for StructuralPerformance of Exterior Windows, CurtainWalls, and Doors by Uniform Static AirPressure Difference,” there shall be no glassbreakage, damage to hardware, orpermanent deformation that would causeany malfunction or impair the operation ofthe unit. Residual deflection of any membershall not exceed 0.4% of its span. Windowsshall be subjected to pressures of 37.5 psffor hung and 60 psf for casement.

• The maximum U-value for the wholewindow shall not exceed the following:

— hung: 0.50 U-value (not less than R-2),and

— casement: 0.40 U-value (not less thanR-2.5).

The U-value shall be calculated usingASTM E 1423, “Standard Practice forDetermining the Steady State ThermalTransmittance of Fenestration Systems,” and\orthe National Fenestration Ratings Council’sNFRC 100-91, “Procedure for DeterminingFenestration Product Thermal Properties.”

Double-glazed units shall have a nominalair space of at least 3/8 in. but not more than1 in. The low-E coating, if present, must have anemissivity value less than 0.40.

The manufacturer of the window mustpresent a copy of a letter from an independenttesting laboratory certifying the performance ofthe window supplied by the manufacturer. Thisletter must state that a window comparable tothe one being used has been tested and meets orexceeds the standards outlined.

Manufacturers of wood or wood-cladwindows must present a written statementdeclaring that the wood is preservative-treatedin accordance with the latest version of


NWWDA Industry Standard I.S.4, “WaterRepellent Preservative Treatment for Millwork.”

It is the installer’s responsibility to obtainthe installation specifications from the

manufacturer of the window being installed andto install, insulate, and finish (paint) the windowaccording to those specifications.


5.5 HVAC Equipment

FURNACES AND BOILERS

The AFUE rating of all new furnaces andboilers—as determined in Sect. 4.2.11, “Heatingand Cooling Equipment ReplacementSelection,” or 4.2.12, “Heating and CoolingEquipment Selection”—shall be specified fornewly purchased units. All new gas-fired unitsshall have intermittent ignition devices (IIDs). Anew condensing furnace that will be installedinside the housing unit shall be asealed-combustion unit that uses 100% outsideair for combustion. A new flue or chimney linershall be specified with the installation of a newfurnace or boiler if it is required to meetbuilding codes, to maintain a proper draft, or toensure material compatibility with the new fluegas conditions. A new flue or chimney linershall be specified for the hot water system if anew condensing system is installed.

The commissioning procedure outlined inthis section shall be specified for all newfurnaces and boilers to ensure correctinstallation and operation of the unit.

AIR CONDITIONERS

The SEER rating as determined inSect. 4.2.11, “Heating and Cooling EquipmentReplacement Selection,” or Sect. 4.2.12,“Heating and Cooling Equipment Selection,”shall be specified for newly purchased units.Specify condensing (outside) units to beequipped with a housing that protects the fins(units shall not have exposed plate-type fins).Specify the location of the outdoor unit so thatthere are no restrictions around it (such asshrubs and decks) that block airflow or promoterecirculation. Specify a clear area around theoutdoor unit of at least 2 ft. Specify the outdoorunit location to be greater than 6 ft from theexhaust of the clothes dryer.

The commissioning procedure outlined inthis section shall be specified for all new air

conditioners to ensure correct operation of theunit.

HEAT PUMPS

Specifications for new heat pumps are thesame as for air conditioners with one addition.Specify that heat pumps with resistance heatersshall have an outdoor thermostat to prevent theresistance heaters from turning on at ambienttemperatures above 45°F or other preselectedtemperature.

The commissioning procedure outlined inthis section shall be specified for all new heatpumps to ensure correct operation of the unit.

INTERMITTENT IGNITION DEVICES

Field-installed IIDs shall be certified by theAmerican Gas Association (see the association’sDirectory of Certified Appliances andAccessories, “Automatic Intermittent PilotIgnition Systems for Field Installation”).

COMMISSIONING AND TUNE-UP OFFURNACES AND BOILERS

The contractor shall commission all newlyinstalled fossil-fuel-fired heating systems andtune up all existing systems by completing thefollowing tasks.

1. Perform a visual inspection of gas- andoil-fired systems to ensure safe operation.Check for the presence of an electricalcutoff switch, proper grounding, insecurewiring, or combustible materials near theflue. Verify the adequacy of combustion air.Inspect the furnace heat exchanger forcracks and any evidence of flame roll-out.Inspect the flue and chimney for structuraldecay, leaks, accumulation of deposits, andthe presence of a flue liner. For fuel-oilsystems, verify the presence of a filter and ashutoff valve in the fuel supply line and the


presence and functional condition of abarometric damper in the flue connection.Inspect the fuel supply line and storage tankfor leaks. Correct all deficiencies found.

2. For furnaces, set circulation fan “off” limitswitches at 90–95°F and high-limit switchesat 200–250°F, or set the switches inaccordance with manufacturerspecifications if they differ. Circulation fan“on” limit switch settings for furnaces aresystem dependent. Choose the lowestpossible temperature setting that avoids“rocking on” or cycling of the fan after theburner has shut off, generally from 120°F to160°F. For boilers, set system operatingtemperatures and high-limit switch settingsto standard recommended values of themanufacturer.

3. Adjust each burner under the guidance ofcombustion analysis to maximize itssteady-state efficiency. Measure thepercentage oxygen reading and net stacktemperature to calculate the steady-stateefficiency. Adjust this efficiency for smokenumber for oil-fired systems. For existingoil-fired systems, targets are to achieve atleast a steady-state efficiency of 80% with aflue gas containing 7% oxygen and a smokenumber 1.

4. Measure the carbon monoxide level in eachburner after the burner has run continuouslyfor 5 minutes. Adjust the burner if carbonmonoxide readings greater than 250 ppmoccur. Adjustments include cleaning burnersand eliminating heat exchangerobstructions. Also, make carbon monoxidemeasurements 5 ft from the space-heatingsystem and in the living area of the housingunit. Readings greater than 5 ppm indicateleakage from the furnace or flue. Identifyand correct the source of the carbonmonoxide leakage in these areas.

5. Use at least one of several methods to ensurethat heat exchangers are not cracked infurnaces. Measure the percentage oxygenreading in the flue immediately before andafter the fan turns on. A change in thereading indicates a cracked heat exchanger.Additionally, observe the burner flame tosee if it changes when the fan turns on.Again, a change indicates a cracked heatexchanger.

6. Limit the temperature rise across the heatexchanger of a furnace to 80°F and the exittemperature of supply air to 160°F bymaintaining adequate airflow. Try to keepthe temperature rise across the heatexchanger within the upper half of the rangespecified by the manufacturer for newequipment. Current airflow can be measuredat return grills using a hand anemometer,measuring the area of the return openingand accounting for the area of the grill if itremained in place while the velocitymeasurements were taken.

7. Perform draft measurements to ensure thatadequate draft is present and that spillage isminimized. Measure the draft with thesystem off first. After turning the system on,record the draft at 1-minute intervals for 3to 5 minutes, as well as the time needed tostop spillage. Spillage can best be observedusing chemical smoke. Drafts of 0.02 to0.06 in. water shall be obtained. Spillageshall stop within 30 seconds.

8. For the condensing system, verify the correctinstallation of the exhaust and air intakepipes. The exhaust pipe must be pitched atleast 1/4 in. per foot so that condensate candrain back to the furnace. Supports must beadequate so that the exhaust pipe does notsag between supports. The exhaust pipemust be sized following manufacturerinstructions. The air intake pipe (if present)must be located away from dryer vents andpower-vented water heaters so that it doesnot draw in contaminated air. Exhaust and


air intake pipes must be run out the sameside of the housing unit and be locatedabove anticipated snow levels.

9. Verify the correct operation of the thermostatby checking the anticipator setting (ifpresent) and the cut-on and cutofftemperatures relative to the set point.

10. Other tasks to be performed include checkingand adjusting the manifold pressure ofgas-fired systems, adjusting belt tensions,checking the condition and operation of thecirculation fan of furnaces, checking thecondition and operation of circulatingpumps of boilers, checking the operation ofzone valves of boiler systems, and using agas detector to identify the presence of gasleaks.

11. Document the commissioning/tune-up resultsby providing the military inspector for theproject with the following information:

• initial and final steady-state efficiencies,• net stack temperature,• oxygen concentration,• smoke number (oil only),• circulation fan “on” and “off” limit

temperatures,• high-limit temperature,• carbon monoxide levels,• temperature rise across heat exchanger,• draft readings, and• deficiencies found and corrective actions

taken.

COMMISSIONING AND TUNE-UP OFAIR CONDITIONERS AND HEATPUMPS

The following tasks shall be accomplishedin commissioning new or tuning up existingequipment.

1. Measure the airflow rate across the indoorcoil. The rate must be 350 to 450 cfm per

ton of cooling capacity for efficientoperation. This rate must be establishedbefore the system can be correctly charged.

2. For new systems that are not precharged,charge the system by weighing in the properamount of refrigerant according tonameplate or manufacturer instructions afteraccounting for the length of refrigerant lines.

3. For all systems, check and adjust therefrigerant charge based on superheat andsubcooling measurements made with thesystem operating in the cooling mode.These measurements give the most reliableresults when the ambient temperature isgreater than 80°F. For heat pumps that mustbe tuned up in the winter, check and adjustthe refrigerant charge based on the hot gastemperature method. Use this method onlywhen conditions prevent the use of thesuperheat and subcooling method. Thecharge shall not be adjusted based onperformance curves or noninstrumentedapproaches.

4. Ensure that the air temperature differenceacross the indoor coil is 15 to 20°F when thesystem is operating in the cooling mode.

5. Perform a visual inspection to ensure safeoperation of the system. Inspect the fuseddisconnect, wiring, contactors, relays,pressure controls, and other electrical safetycircuits. Tighten electrical connections asneeded and correct any deficiencies found.

6. Verify the correct operation of the thermostatby checking the anticipator setting (ifpresent) and the cut-on and cutofftemperatures relative to the set point. Forheat pumps, check the operation ofresistance heaters to ensure that they arewired correctly to their control circuits (theycycle correctly, are staged correctly, and arenot on all the time). Also, test the defrostoperation of heat pumps.


7. Other tasks to be performed include checkingthe voltage and amperage to all motors,cleaning the indoor fan if dirt has built up(especially if the airflow across the indoorcoil is less than 350 cfm per ton of coolingcapacity), checking bearings, lubricating allmoving parts as required, checking andadjusting belt tension, inspecting andcleaning the condensate drain if necessary,and cleaning the outdoor and indoor coils ifnecessary. As an option, perform a meggartest of hermetically sealed compressors tocheck the condition of electrical insulation.

8. Document the commissioning/tune-up resultsby providing the military inspector for theproject with the following information:

• airflow rate across the indoor coil and thecapacity of the unit;

• initial and final measurements used tocharge or check the charge of the system;

• temperature difference across the indoorcoil; and

• deficiencies found and corrective actionstaken.


5.6 Air Distribution System Repair andConstruction Specifications

Use the following materials and proceduresto install new ductwork and to correct identifiedinfiltration deficiencies in existing ductwork.

DUCT MATERIALS

New duct systems or replacement ductsshall be fabricated from sheet metal, rigidfiberglass, or fiberboard using the followingguidelines. Systems constructed entirely offlexduct are not permitted. However, flexductsmay be used as branch connections to supplyregisters in only those cases where spacelimitations and short distance runs makeinstallation of metal or fiberboard ductsprohibitively costly or difficult.

Mechanical fasteners shall be used to secureall joints between sections of duct, especiallybetween sections of air ducts and plenums, ductsand terminal fittings, connections at the airhandler equipment, connections of branch ductsto main trunk ducts, and duct sectionsconstructed of different materials. Materialsintended to seal against air leaks— such asmastics, caulks, and fiberglass tape—shall notbe used to fasten sections of duct together.

Metal Ducts

Install metal ducts according to DuctConstruction Standard—Metal and Flexible(SMACNA 1985, first edition). Seal joints andconnections in metal ductwork in accordancewith Table 5.1. Fasten transverse joints that arefriction-fitted with at least three metal screwsequally spaced around the joint. Insulate metalducts in unconditioned spaces (e.g., attics, crawlspaces, garages) to an insulation value of at leastR-6. Wrap the outside of ducts with foil-facedfiberglass batts that are attached withmetal-faced duct tape.

Rigid Fiberglass (Fiberboard) Ducts

Fabricate fiberboard ducts from ductboardwith metal facing on the outside surface.Fiberboard ducts shall be either round(preformed off site) or rectangular (formed onsite from precut, standard-size sections). Installfiberboard ducts according to Fibrous GlassDuct Construction Standards (SMACNA 1992,sixth edition). Fiberboard duct sections shall befastened together using clinching staples.Fiberboard shall provide an insulation value ofat least R-6. Lap and seal on-site joints with acombination of fiberglass mesh and mastic (seeTable 5.1).

Flexible Ducts (Flexducts)

Prefabricated, round ducts with 2- to 12-in.diameters shall each have an inner, flexible,nonporous core of plastic supported by a metalcoil for strength. An outer liner shall enclosefiberglass insulation between the core and theouter liner to provide an insulation level of atleast R-6. Acceptable flexduct shall be air-ductrated by National Fire Protection Association90B, “Warm Air Heating and Air ConditioningSystems,” 1989, and shall meet the testingrequirements of Standard UL-181 forfactory-made air ducts and air connectors.

Install flexduct according to DuctConstruction Standard—Metal and Flexible(SMACNA 1985, first edition). Seal jointsbetween flexducts and metal collars and registerboots at the inner core with approved mastic orjoint sealant as directed in Table 5.1. Installflexducts so that their length is minimized.Flexduct bends shall not exceed 90 degrees andmust have a radius greater than one diameter.Flexducts shall be mechanically fastened to allmetal ducts and metal fittings using drawbandsthat are preferably metal. Flexducts must befastened to fiberboard ducts using twist-in


Table 5.1. Sealing requirements for duct systems

Duct joint or connectionSystem replacement

and/or extension System repair

Transverse joints in round metalducts, consecutive lengths

Screw metal joint, masticand fiberglass tapea seal

Screw metal joint, masticand fiberglass tapea seal

Snap-lock joints in round orrectangular metal ducts

None None

Metal collar to metal or fiberboardduct or junction box

Mastic Mastic

Metal elbow swivel joints None None

Joints in fiberboard ducts Mastic plus fiberglass tape Mastic plus fiberglass tape

Return main connection to returngrill

Secure with screws andcaulk gaps

Add blocking material asnecessary, caulk gaps

Return duct joints Rectangular metal—nojoint sealSheetrock—not allowed

Rectangular metal—nojoint sealSheetrock—mastic joints

Air handler return platform Sheetrock to framing,caulk or mastic joints

Sheetrock or ductboard toframing, caulk or masticjoints

Building return cavities Rectangular metal duct Mastic or caulk joints

Flexduct to metal collars atconnections or duct boots

Seal inner liner to collarwith mastic, minimum1-in. overlap; use bandaround outer liner.b

Seal inner liner to collarwith mastic, minimum 1-in.overlap; use band aroundouter liner.b

Plenums to air handler Mastic or caulk Mastic or caulk

Air handler penetrations Metal-faced tape Metal-faced tape

Panned floor joist returns Not allowed Remove metal pan andcaulk all joints; replacemetal pan and caulk joints.

Floor truss cavity orstud bay cavity returns

Remove when possible;replace with rectangularmetal ductwork.

Remove when possible;replace with rectangularmetal ductwork.

Floor cavity returns Mastic or caulk jointsand penetrations

Mastic or caulk jointsand penetrations

aUse for gaps more than 1/8–1/4 in. wide.bMetal or nylon bands are required in attics with temperatures above 120°F.


(screw attachment) bend-tabs or screw-tabs andflanges.

JOINT SEALANTS

Apply the following sealants as specified inTable 5.1 after thoroughly removing moisture,dust, dirt, oil, grease, or other substances thatmay diminish the bond of the sealant material.

Mastics and Fiberglass Tape (FiberglassMesh)

Use water-based mastics with fiberglasstape to seal and provide strength to all joints.Water-based mastics are preferable topetroleum-based mastics because of shortercuring times, easier cleanup, and more“forgiving” application characteristics. Whenused with fiberglass tape, mastic can seal andprovide strength to repairs of practically anyconfiguration. Mastic should generally beapplied over the entire joint between matedsurfaces and must not be diluted. Use fiberglassmesh when gaps are larger than 1/8 in.

Mastic sealants shall conform to thefollowing safety requirements of ULStandard 181, Class 1:

• a flame spread rating of less than 25, and• a smoke development rating of less than 50

in the dry, final state.

In addition, the sealants shall conform tothese characteristics:

• a solids content greater than 50% to reduceshrinkage on drying;

• the capability to adhere to manysurfaces—sheet metal, drywall, fiberboard,concrete, wood, and plastic; and

• a temperature range that includes thehighest and lowest temperatures likely to beencountered.

Caulking

Long-lasting (20 years or more) siliconecaulking materials are required for sealing leaks

in duct systems. This material shall have thesame safety requirements as mastic sealant andshall be UL rated.

Gasketing

Joints can be sealed using gasketingmaterial placed between the surfaces to bemated and fastened with sufficient force tocompress the gasketing material. All voids andcracks at the joint must be filled by thegasketing material.

Duct Tape

Metal-faced pressure sensitive orheat-activated tapes that meet UL Standard 181shall be used only for sealing penetrations andjoints on equipment where access formaintenance is required. Fabric duct tape or tapewith rubber-based adhesives is prohibited as asealing material except as a temporary materialto support a joint during fabrication. Remove allfabric tape before the completion of theinstallation. Pressure-sensitive tape must beapplied using a squeegee (rather than by hand),and to surfaces that are at the propertemperature as prescribed by industry standards.

INSTALLATION PROCEDURES FORNEW DUCTWORK

Size duct systems according to theAir-Conditioning Contractors of America(ACCA) Manual J, and design duct systemsaccording to the ACCA’s Manual D. Submitdesign forms to the contracting officer. Followthe previously outlined material specificationsfor ducts and joint sealants, the requirements inTable 5.1, and the procedures outlined below.

Return Ducts

Return ducts shall be constructed with thefollowing additional requirements:

1. Locate return ducts in the conditioned spacewhenever practical to minimize exchangewith unconditioned air.


2. Use of building cavities, building framing,floor truss cavities, and panned floor joistsfor return ducts is prohibited.

3. Enclose raised floor platforms and other returnplenums for furnaces and air handlers withdrywall and seal all penetrations and jointswith mastic or caulk.

4. Provide a separate return duct for each level ofa multilevel unit.

5. Attach and seal return ducts to the wall atreturn grills to isolate building cavity airfrom the return duct.

Supply Ducts

Supply ducts shall be constructed with thefollowing additional requirements:

1. Locate supply ducts within the conditionedspace whenever practical.

2. Extend duct boots at supply registers throughthe wall, ceiling, or floor material withregisters tightly fitted to duct boots toprevent loss of conditioned air to thebuilding cavity.

Air Handler

Use the following procedures to eliminateair leaks at the air handler:

1. Seal penetrations, seams, and gaps in the airhandler cabinet with metal-faced duct tapeor “tape applied mastics” (foil tapes with15 mil or thicker butyl adhesive).

2. Seal joints between the air handler cabinet andthe main supply and return ducts or plenumswith mastic or caulk.

Supports

Support ductwork at intervals of no morethan 5 ft. Fiberboard ducts and flexducts inattics may require additional support when

elevated above floor joists. Supports shall bemetal hangers or other materials that will notpenetrate the duct surface.

REPAIR PROCEDURES

Follow the material specifications for ductsand joint sealants outlined previously. Wheninsulation on sheet-metal ductwork is eitherdamaged or nonexistent, attach foil-facedfiberglass batts rated at R-6 or more withmetal-faced duct tape. Follow the sealingrequirements for “system repair” specified inTable 5.1 to repair existing ductwork. Pull backor remove insulation to expose joints. Removeall fabric duct tape encountered.

Supply Ducts

Use the following procedures to repairexisting supply ducts:

1. Seal gaps between supply boots and supplyregisters with fiberglass tape, mastic, andblocking material to prevent loss ofconditioned air.

2. Fasten joints in round metal ducts that leakfrom lack of sealant (i.e., that are fastenedwith fabric tape only) with sheet metalscrews and seal with mastic and fiberglasstape.

Return Ducts

Use the following procedures to repairexisting return ducts:

1. Seal gaps between return ducts, return grills,and the wall at return grills to isolatebuilding cavity air from the return duct.

2. Seal the joints in return ducts made of drywallwith mastic where they are accessible.

3. Interior walls under a raised floor furnace orair handler platform shall have drywall orductboard securely attached to the framing.


Seal all penetrations and joints with masticor caulk.

4. Replace panned floor joist returns with newductwork or seal all interior and exteriorjoints with caulk or mastic. Block off anyconnections to building cavities.

Air Handler

Use the following procedures to repair airleaks at the air handler:

1. Seal penetrations in the air handler cabinetwith metal-faced duct tape or “tape appliedmastics” (foil tapes with 15 mil or thickerbutyl adhesive).

2. Seal joints between the air handler cabinet andthe main supply and return ducts or plenumswith mastic or caulk.


5.7 Air Distribution System Performance Testing

DIAGNOSTIC TESTING

Randomly selected new and/or revitalizedhousing units shall be tested to determine thecompliance of the unit with the allowableair-leakage rate specified for the air distributionsystem. Units shall be selected by the programmanager. Testing shall be performed by a firmqualified to perform inspections using blowerdoors in accordance with procedures specifiedin Appendix E for air distribution systemtesting. The testing firm shall be independent ofthe installing contractors or equipment suppliersfor this project. The specifications provided inAppendix B can be used to hire a qualified firm.

PERFORMANCE REQUIREMENTS

Air distribution system air leakage shall beless than or equal to 150 cfm when the system ispressurized at 50 Pa.

AAppendix

ENERGY INSPECTION FORMS FORMILITARY FAMILY HOUSING UNITS

MILITARY FAMILY HOUSING: ENERGY INSPECTION FORMS

IDENTIFICATION

Installation name: ______________________________________________Housing unit ID: _______________________________________________Housing unit address: ___________________________________________Inspector:_____________________________________________________Affiliation:____________________________________________________Inspection date: ________________________________________________

GENERAL

Type:___________

SFD—single-family detached MFS—small (2–4 units) multifamilySFA—single-family attached MFL—large (>4 units) multifamilyMH—manufactured or mobile home

A single-family housing unit is a structure that provides living space for one household or family. Thestructure may be detached, attached on one side, or attached on two sides. An attached house is considered a single-family houseas long as the house itself is not divided into more than one housing unit and has an independent outside entrance. Asingle-family house is contained within walls that go from the basement (or ground floor, if there is no basement) to the roof. Amobile home with one or more rooms added is a single-family house. Side-by-side duplexes (twins) and quad-plexes (oftenfound at military installations) are typically single-family attached houses.

A small multifamily house or building is a structure that is divided into living quarters for two, three, or four families orhouseholds. This category also includes houses originally intended for occupancy by one family (or for some other use) that havesince been converted to separate dwellings for two to four families. Typical arrangements in these types of living quarters areseparate apartments downstairs and upstairs, or one apartment on each of three or four floors. Over-and-under duplexes aretypically in this category.

A mobile or manufactured home is a structure that has all the facilities of a dwelling unit but is built on a movable chassis. It maybe placed on a permanent or temporary foundation and may contain one room or more. If rooms are added to the structure, it isconsidered a single-family home.

Are the following systems shared with other housing units:

space-heating system_____(Y, N)space-cooling system_____(Y, N)water-heating system_____(Y, N)

If SFA, number of attached housing units: _____ (NA, 1, 2, etc.) (typically 2 or less)

If MFS or MFL, number of housing units: Beside_____Above_____Below_____

ENERGY INSPECTION FORMS FOR MILITARY FAMILY HOUSING UNITS A-1

Housing unit ID:________

FLOOR AREAS AND VOLUMES

Floor

Totalareaa

(ft2)

Intentionallyheated areaa,b

(ft2)

Intentionallyair-conditioneda,b

area(ft2)

Averageceilingheightc

(ft)Volume

(ft3)

Basement

First floor

Second floor

All other floors

Totals

aAreas are gross areas that include internal storage closets, etc. rather than net areas as defined by the military.

bAn intentionally conditioned space is one with equipment and/or distribution outlets designed to maintain a desiredtemperature in the space. An unintentionally conditioned space is one that is conditioned primarily from equipmentjacket and/or distribution losses (there is little control over the resulting temperature). A space is not conditioned ifthere is no source to alter the natural temperature of the space. For example, a basement heated primarily fromequipment jacket and/or distribution system losses is an unintentionally conditioned space rather than anintentionally heated space. A window air conditioner cools only the room the unit is installed in, not adjacent rooms.If a space was designed to be intentionally conditioned but is maintained by the occupant in an unconditioned state(by closing registers and doors, for example), the space should still be considered a conditioned space.

cFloor heights used to calculate volume are floor to floor, except for the top floor, which is floor to ceiling. Forcathedral ceilings, use average of maximum and minimum heights.

Number of intentionally heated stories:________(1, 1.5, 2, 2.5, etc.)

Number of intentionally cooled stories:________(1, 1.5, 2, 2.5, etc.)

A-2 ENERGY INSPECTION FORMS FOR MILITARY FAMILY HOUSING UNITS


THERMAL BOUNDARY

Provide a sketch of the floor plan(s) and the sections of the unit being revitalized indicating the location ofthe thermal boundary. Identify insulated and uninsulated areas along the boundary.



EXTERIOR WALLS

Walllocation(keyedto floorplans)

Walltype

Wallexposure

Exteriorfinish

Grosswallarea(ft2)

Existinginsulatedsheathing

Existing cavity insulationVaporbarrierpresent(Y,N)Type

Thickness(inches)

Shared walls found in duplexes, quad-plexes, and multifamily structures are not exterior walls.

Wall type (type of load-bearing structure):FR—frame, BL—block, ST—stone or masonry, X—other

Wall exposure:O—outside, N—nonconditioned attic space, B—buffered space (garage, etc.)

Exterior finish:WO—wood or masonite, AL—aluminum, steel, or vinyl, ST—stucco, BR—brick orstone, AS—asphalt shingle, X—other, N—none

Insulated sheathing:Y—yes (present), N—not present, U—unknown

Insulation type:BC—blown cellulose, BF—blown fiberglass, FB—fiberglass batt, BRW—blown rockwool, RWB—rock wool batt, RB—rigid board or foam, X—other, N—none



FOUNDATION SPACES

Joist Perimeter Wall

TypeSpacestatus

Areaa

(ft2)

Insulationthickness(inches)

Lengthb

(ft)Percentc

insulatedHeightd

(ft)

Percentaboveground

Existinginsulation

typeThickness(inches)

IS

US

aFor slab-on-grade, the area of the intentionally conditioned slab floor.bDo not include perimeter bordering another foundation space.cThe percentage of band (rim) joist length that is exposed to the outside and insulated.dHeight of basement or crawlspace wall; an estimated average if the height is not uniform.

Type:B—basement, C—crawl space, IS—insulated slab, US—uninsulated slab

Space status:NC—nonconditioned space, IC—intentionally conditioned space, UC—unintentionallyconditioned space

Existing wall insulation type:BC—blown cellulose, BF—blown fiberglass, FB—fiberglass batt, BRW—blown rock wool,RWB—rock wool batt, RB—rigid board or foam, V—vermiculite, X—other,N—none

Vapor retarder present on crawl space floor?________(Y, N, NA)



ATTICS

UNFINISHED ATTIC AREAS

Existing insulation

Attictype

Floor areaa

(ft2) TypeDepth

(inches)

Radiant barrierpresent(Y, N)

Vapor barrierpresent(Y, N)

FINISHED ATTIC AREAS

Existing insulation

LocationAttictype

Areaa

(ft2) TypeDepth

(inches)

Radiantbarrierpresent(Y, N)

Vaporbarrierpresent(Y, N)

Outer joist

Collar beam

Kneewall

Roof rafteraAreas must be adjacent to intentionally or unintentionally conditioned spaces only. For example, the area

above an unconditioned garage should not be included.

Attic type:F—floored, U—unfloored, C—cathedral, F—flat roof

Existing insulation type:BC—blown cellulose, BF—blown fiberglass, FB—fiberglass batt, BRW—blownrock wool, RWB—rock wool batt, RB—rigid board or foam, V—vermiculite,X—other, N—none

Attic access hatches insulated?_____ (Y, N, NA)

Attic access hatches weatherstripped?_____(Y, N, NA)

Comments concerning blocking, uniformity of insulation depth, and attic ventilation: _____________

_____________________________________________________________________________________



INFILTRATION

BASEMENT/CRAWL SPACE

Inspectionpoint

Infiltrationproblem

Evaluation of conditions

Floor penetrations—electrical service Gaps around conduits

Floor penetrations—plumbing service Gaps around piping

Floor penetrations—air ducts Gaps around ducts

Floor penetrations—general Holes for air leakage

Sill plate No seal at sill plate

MAIN FLOOR(s)

Exterior wall penetrations under sinks and appliances

Holes and gaps

Exterior walls Holes and gaps

ATTIC

Ceiling penetrations—electrical service Gaps around conduits

Ceiling penetrations—plumbing service Gaps around piping

Ceiling penetrations—air ducts Gaps around ducts

Ceiling penetrations—general Holes for air leakage — at top of interior or exterior walls — at dropped ceilings — other

Plumbing and duct chaseways Attic bypasses

Attic hatch Poor seal



WINDOWS AND GLASS DOORS

Wallcode

Glazingtype

Frametype

Stormwindow

type

Stormwindowcondition

Height(inches)

Width(inches)

Weather-stripping

Numberof

windows

Totalarea(ft2)

Glazing type:SP—single pane, DP—double pane, TP—triple pane, GB—glass block, TE—temporary

(cardboard, plastic, etc.), X—other

Frame type:W—wood, M—metal, MTH—metal with thermal breaks, V—vinyl, X—other, N—none

Storm window type:W—wood, M—metal, X—other, N—none

Storm window condition:A—adequate, R—needs replacement

Weather stripping:A—adequate, R—needs replacement



EXTERNAL DOORS

Condition

Wallcode

Doortype

Height(inches)

Width(inches)

Storm door(Y, N) Storm door Weatherstripping Threshold

Door type:H—hollow core wood, S—solid core wood, P—paneled wood, M—metal,MTH—metal with thermal break, X—other

Condition:A—adequate, R—needs replacement



SPACE-HEATING SYSTEM

Space-heating system types:Central systems:1—forced air furnace, 2—gravity furnace, 3—steam boiler, 4—hot water boiler withradiators/convectors, 5—hot water boiler for slab heating, 6—heat pumpFossil fueled in-space heaters:7—room heater, 8—forced-air wall furnace, 9—gravity wall furnace, 10—forced airfloor furnace, 11—gravity floor furnace, 12—vaporizing pot heater (oil and kerosene),13—portable keroseneElectric in-space heaters:14—wall, 15—floor, 16—baseboard, 17—ceiling radiant (imbedded cable), 18—wallor floor radiant (imbedded cable), 19—portable (cord-connected), 20—window heat pump

Fuel:NG—natural gas, P—propane, O—oil, E—electricity, X—other

Location:NC—nonconditioned space, IC—intentionally conditioned space,UC—unintentionally conditioned space

Other efficiency measures:V—vent damper, I—intermittent ignition device, F—flame retention burner,O—outdoor temperature reset (boilers only), G—gas power burner, X—other,N—none

Auxiliary Systems

Type Fuel Number

Primary System

System type

Fuel type

System age years

Location in housing unit

Manufacturer

Model

Input rating

Output rating

Efficiency (rated) %

Pilot light (Y,N,NA)

Pilot light on over summer (Y,N,NA)

Other efficiency measures



AIR CONDITIONER OR HEAT PUMP

Systemtype Manufacturer Model

Age(years)

Input(watts)

Output(Btu/h) Efficiency

System type:CACS—central A/C split unit CACP—central A/C package unitCHPS—central heat pump split unit CHPP—central heat pump package unitWAC—window A/C WHP—window heat pumpEC—evaporative cooler GP—gas packX—other

Are there problems of air recirculation at the outdoor coil? ________(Y, N, NA)If yes, describe:______________________________________________________________

____________________________________________________________________________________________________________________________________________________________

Is there plant material next to the outdoor coil that could contribute to clogging of the coil?________ (Y, N, NA)

HEATING AND COOLING SYSTEM CONTROLS

Thermostats operating correctly?________(Y, N, NA)

Setback thermostat installed?________(Y, N)

If yes, does it have automatic switchover between heating and cooling?_____(Y, N)

Is the thermostat located in a central part of the housing unit, where the temperature would berepresentative of the primary living area of the unit?________(Y, N)

Is the thermostat located on an interior wall?________(Y, N)

Does the wall cavity behind the thermostat allow air to circulate from the attic or basement/crawlspace?________(Y, N)



AIR DISTRIBUTION SYSTEM

Ductfunctiona

Ducttypeb Locationc

Joint sealconditiond

Structuralintegritye

Insulationconditionf Comments

aDuct function: SP—supply plenum; ST—supply trunk; SB—supply branch; RP—return plunum; RD—returnduct.

bDuct types: DB—duct board, SM—sheet metal, FD—flexduct, PFJ—panned floor joists, SBC—stud bay cavities, X—other

cLocation: A—attic, CB—conditioned basement, UB—unconditioned basement, H—hallway ceiling, C—crawlspace, G—garage

dJoint condition: G—good; F—fair, minor leakage; D—deteriorated, needs replacementeStructural integrity: G—good, F—fair, minor leakage; D—deteriorated, needs replacementfInsulation condition: G—good; F—fair, minor repairs, D—degraded, replace, N—none.


Housing unit ID:__________

DOMESTIC WATER-HEATING SYSTEM

Type (SA—stand alone, T—tankless, X—other)

Fuel (NG—natural gas, O—oil, E—electricity, X—other)

Age years

Manufacturer

Model

Upper heating rate (kW, Btu/h)

Lower heating rate (electric systems only) kW

Capacity gallons

Location (NC—nonconditioned, IC—intentionally conditioned, UC—unintentionally conditioned)

External insulation wrap (R-values or inches)

Are hot and cold water lines connected to proper fittings? (Y, N)

Is a heat trap installed on the cold water line? (Y, N)

Is a heat trap installed on the hot water line? (Y, N)

Hot water pipes insulation (R-value or thickness)

Length of hot water line insulated (feet)

DOMESTIC WATER DISTRIBUTION

Cold water flow at showerhead number 1 gpm

Cold water flow at showerhead number 2 (or NA) gpm

Aerators present on all sink faucets (Y, N)

Are water lines located outside the conditioned area? (Y, N)

If yes, are lines insulated or protected using heating tapes? (Y, N) If no, identify uninsulated or unprotected lines:



EXHAUST SYSTEMS

Do all exhaust systems (e.g., range hood, bathroom fans, dryer vent, plumbing vents) vent directly to theoutside?________(Y,N)

If no, describe:__________________________________________________________

Do the bathroom exhausts, dryer, and range hood have:

Bathroom exhaust Dryer Range hood

Bath 1 Bath 2 Bath 3

Dampered vents? (Y,N)Free moving dampers? (Y,N)Positive seal? (Y,N)Fan/duct leaks? (Y,N)

APPLIANCES

Is there a gas line currently running to the house? (Y, N)________

If yes, is there a gas line currently running to the kitchen? (Y, N)________

Does the kitchen space allocated for the refrigerator allow air to circulate freely around the condensorcoils? (Y, N)________



LIGHTING

Room

Location:wall (W)

ceiling (C)Lamptype

Numberof lamps

Totalwatts

Controldevice

Condition andComments

Living room

Dining room

Family room

Den

Hall (down)

Hall (up)

Bath 1

Bath 2

Bath 3

Kitchen

Utility room

Storage room

Stairs

Bedroom 1

Bedroom 2

Bedroom 3

Bedroom 4

Bedroom 5

Basement

Attic

Front entry (exterior)

Rear entry (exterior)

Porch (exterior)

Outdoor area lights

Outdoor storage

Garage

Lamp type:CF—compact fluorescent; FL—fluorescent; H—halogen; I—incandescent.

Control device:S—switched outlet; TWS—three-way switch; D—dimmer; PC—pull chain.



SITE IMPROVEMENTS

Provide a sketch of the typical site(s) for each type of unit being revitalized showing

• vegetation that should be retained and protected during construction;• vegetation that should be removed or pruned because of its proximity to heat pumps, air conditioners,

etc.; and• pavement that is unneeded and could be removed, or is in poor condition and could be relocated

during revitalization (at installations with significant summer air conditioning requirements).


BAppendix

BLOWER-DOOR INSPECTORSELECTION GUIDE

Blower-Door Inspector Selection Guide

PURPOSE OF TESTING

Inspections of new and existing housingunits using a blower door will be performed tomeasure the air-leakage rate of the housing unitand air distribution system (if present).Envelope leakage locations that contributesignificantly to infiltration will be identified inexisting housing units that will retain most ofthe exterior envelope and current interiorconfiguration following revitalization. Airdistribution systems (if present) will beevaluated if the system is to be retainedfollowing revitalization. This evaluation willidentify the location and type of major ductleaks that must be repaired during revitalization.

REQUIRED EXPERIENCE

The contractor must be proficient inblower-door testing and inspections of envelopeand air distribution system air leakage and musthave performed blower-door-guided evaluationsof envelope and duct leakage in at least 20single-family and/or multifamily residentialbuildings during the past year to be consideredfor this contract. The contractor shalldemonstrate proficiency and experience in allfacets of blower-door testing (measuringenvelope and duct leakage and identifyingenvelope and duct-leakage sites) by providing asummary of its relevant experience inblower-door testing of residential buildings overthe last three years. The types of programsblower-door testing was performed for shall bedescribed. For each program, the number ofunits inspected by the contractor shall be listed,the type of testing and inspections performed bythe contractor shall be described, testingprotocols and data forms followed by thecontractor in performing the work shall beprovided, and reports prepared by the contractorsummarizing the inspection results shall be

provided (if they are not confidential). Thecontractor shall also provide the name, address,and phone number of the most recent fivecustomers or purchasing agents.

Personnel who will perform the work underthis proposal must be identified. Theirinvolvement in the blower-door testingperformed by the contractor previouslydescribed and other relevant blower-doorinspection experience must be clearly described.Relevant training received by each personnelshall also be listed.

REQUIRED AND OPTIONALEQUIPMENT

The contractor must verify that it willprovide, as a minimum, the followingequipment required for blower-door testing:

• a calibrated blower door that can provide aflow rate of at least 3,000 cfm against 50pascals (Pa) of back pressure and with a fanorifice and pressure gauge system calibratedto 10% accuracy;

• a calibrated airflow measurement systemcapable of testing the airtightness of just theair distribution system in a housing unit,that can provide a flow rate of at least 750cfm against 50 Pa of back pressure, and thathas a fan orifice and pressure gauge systemcalibrated to 10% accuracy;

• a calculator/computer with appropriatesoftware to perform least-squares and erroranalyses of blower-door data and tocalculate a flow rate at 25 and 50 Pa, theeffective leakage area, and the exponentialcoefficient “n” and coefficient ofdetermination (R2) of the regression; and

• synthetic smoke generators for tracingairflow through leakage sites in airdistribution systems and building envelopes.

BLOWER-DOOR INSPECTOR SELECTION GUIDE B-1

The contractor should also indicate theavailability of the following optional, butdesirable, equipment:

• a digital pressure gauge with at least a 60-Parange and self-zeroing capability and

• a pressure pan(s) to allow measurement ofindividual duct pressures with the housingunit depressurized.

B-2 BLOWER-DOOR INSPECTOR SELECTION GUIDE

CAppendix

SPECIFICATION FOR MEASURINGHOUSING UNIT INFILTRATION RATE

Specification for Measuring Housing UnitInfiltration Rate

The total infiltration rate of a newsingle-family detached housing unit will bemeasured with a blower door to determine itsnatural air changes per hour followingconstruction. Similarly, the total infiltration ratewill be measured in an existing single-familydetached housing unit either beforerevitalization, if a significant portion of theexterior envelope and current interiorconfiguration will be retained, or followingextensive “gut” rehabilitation. An infiltrationrate for attached housing units cannot bemeasured using this procedure.

PREPARATION FOR TESTING

Identify on the Housing Unit Air-LeakageMeasurement Form the installation at which theunit is located. Assign a unique identificationnumber to the housing unit, or use theidentification number previously assigned to thehousing unit if an energy inspection wasperformed by the A/E. Document the address ofthe inspected unit, inspector, and inspection date.

Prepare the house as follows for blower-door inspection testing:

• Close all windows and outside doors.• Fill plumbing traps with water (especially

floor drains or other seldom-used traps).• Close the damper and outside air supply to

the fireplace (if present).• Close and secure the attic access hatch.• Turn off all air handler and exhaust fans.• Open all supply and return registers (if

present).• Remove filters from the air distribution

system (if present).• Turn off all combustion appliances.• Close doors to unconditioned utility closets

or other unconditioned spaces such asunconditioned basements.

• Open all interior doors (except for closets)so that all interior conditioned space isconnected, including conditionedbasements. If only portions of the basementare conditioned, open all doors necessary toconnect these conditioned basement areaswith other conditioned areas.

Record on the Housing Unit Air-LeakageMeasurement Form that the housing unit wasprepared for testing. Note the exclusion/inclusion of the basement (if present) asconditioned space and any other special orunusual situations encountered in preparing theunit for testing.

Identify the climate zone for the housingunit from Fig. C.1, the height of the housing unit(number of stories), and local shielding class.Assign correction factors for each of thesecategories as indicated on the Housing Unit Air-Leakage Measurement Form. Calculate theinterior volume of the intentionally conditionedspace of the housing unit, or obtain it from theA/E if the unit has already been audited.

Keep all equipment at a temperature asclose to 70°F as possible while in transit, andbring it into the house immediately upon arrival.Set up the equipment following themanufacturer’s instructions and as specified inthe following:

• Deploy one thermometer outside away fromthe door in a shaded area and one inside inthe same room as the blower door.

• Install the fan on an exterior door fordepressurizing the house. The chosen doormust be free of wind interference andobstructions for at least 4 ft upstream of thefan and should be centrally located.

• Check for leaks around the fan and door.• Install the hose measuring the outside

pressure out of the direct flow of air throughthe blower-door fan. Multiple outside hoses

MEASURING HOUSING UNIT INFILTRATION RATE C-1

or pressure equalizing boxes must not beused.

• Set up and level the gauges inside the houseand out of the direct flow of air through theblower-door fan. Zero the gauge to be usedto measure airflow through the fan afterremoving all hoses from the gauge so thatboth pressure taps are exposed to room air.

• Connect all hoses making sure all hosefittings are tight and that hoses are notpinched or obstructed. Trim or tighten hosesas necessary. If a hose is used to measurethe inside pressure, ensure that it is out ofthe direct flow of air through theblower-door fan.

• Cover the fan opening as recommended bythe manufacturer (using a “shower cap”provided by the manufacturer, plugging ortaping all holes with the orifice plate on, orsome other equivalent technique).

• Zero the gauge used to measure pressuredifference across the house envelope toremove the natural pressure difference that

may exist between the inside and the outsideof the house because of thermal or windeffects.

• Remove the fan opening cover.

Briefly walk through the house whilemaintaining a negative pressure differenceacross the house of 20-30 Pa to check forpreviously undetected operable openings in theenvelope (i.e., open windows, attic hatches,dampers) and other significant sources of airleakage. Identify on the Housing Unit Air-Leakage Measurement Form any unusualsources of air leakage. In addition, look forindications of weak areas (e.g., loose plaster,suspended ceilings, or windows) that could bedamaged with increased negative pressures.

TEST PROCEDURE

Record the following information on theHousing Unit Air-Leakage Measurement Form:

Fig. C.1. Climate correction factor, “C,” for calculating average infiltration rates in North America.

C-2 MEASURING HOUSING UNIT INFILTRATION RATE

• Indoor and outdoor temperatures.• The average wind speed and maximum

wind gust. Deploy the measuring devicethree to five building heights away frombuildings and other major obstructions, andface it into the wind. Average wind speedgenerally should not exceed 10 mph; greaterspeeds and gusty wind conditions can causedifficulty in obtaining quality air-leakagemeasurements.

A test entails making measurements at thefive pressure stations identified on the HousingUnit Air-Leakage Measurement Form. Thepressure stations refer to putting the housingunit in a depressurized mode. If the maximumpressure stations cannot be achieved, then makemeasurements at as many of the assignedpressure stations as possible. Substitute anintermediate pressure station for every listedpressure station that cannot achieved. Forexample, if the 60 Pa pressure station cannot beachieved, add an intermediate pressure stationof 35 or 45 Pa to the test procedure. Makemeasurements starting at the highest pressurestation and proceeding in descending order.

For blower doors with orifice plates or othermeans of reducing the size of the fan opening(plugging holes in a cover plate, etc.) to obtaingreater accuracy at low flows, at least one (andpossibly two) changes in fan opening sizeshould be expected during any particular test.The initial fan opening size should be the largestallowed by the blower-door manufacturer. Withthe fan in this configuration, attempt to make ameasurement at the highest pressure station. Ifthe measured flow is less than the rangerecommended by the manufacturer for theinstalled configuration, reduce the size of thefan opening until the measurement can be made.As measurements are made at lower pressurestations, change to the next smallest fan openingsize when measured flows are less than therange recommended by the manufacturer for theopening size.

Make measurements at each pressure stationin the following manner:

• Lower the house to about 5 Pa below thedesired pressure. Then slowly increase thepressure until the desired pressure isreached. If the pressure is overshot, lowerthe pressure again to 5 Pa below the desiredpressure and repeat the process.

• Tap the gauges continuously while adjustingthe pressure up to the desired station, as thestored spring energy will cause the gaugeneedles to jump slightly.

• Set the gauge needle on the indicatedpressure stations, within 2 Pa.

• After waiting 30 seconds for theblower-door readings to stabilize, record theactual house pressure reading, the fanpressure and/or flow rate reading, and fanopening configuration on the Housing UnitAir-Leakage Measurement Form. Whenlining up the gauge needle with the markson the gauge, read the gauge from directlyin front of it to avoid parallax. Always takereadings off the gauge with the lowest rangepossible. For example, when measuring aflow pressure of less than 125 Pa, read froma gauge with a range of 0–125 Pa ratherthan one with a range of 0–750 Pa. Takeextreme care in recording all data points, astests with unacceptable levels of accuracymust be repeated (see “Analyses” section inthis appendix).

• Record the indoor temperature aftermeasurements have been made at allpressure stations.

ANALYSES

Perform a linear regression of the datacollected at the five pressure stations aftercorrecting the measured airflow rates fordifferences in air density using the followingmodel:

Q = C(∆P)n .

The linear regressions must be performedconsistently with the analysis procedure andequations outlined in Appendix C of StandardCAN/CGSB-149.10-M86 of the Canadian


General Standards Board, and the airflow ratecorrections for air density must be performed inaccordance with Appendix D of this samestandard. These analyses are usually performedby the computer program provided by theblower-door manufacturer.

The series of measurements must berepeated if the flow exponent (n) is less than 0.5or greater than 1.0, the correlation coefficient (r)is less than 0.990, the percentage error in theflow data at each pressure station is more than5%, the relative standard error of the estimatedflow at 10 Pa is greater than 7%, or the relativestandard error of the estimated flow at 4 Pa isgreater than 10%. These numbers are usuallycalculated and output by the computer programprovided by the blower-door manufacturer.Before redoing a test, examine all hoses andfittings for leakage and carefully re-zero thegauges, as these could be the cause of excessiveerror.

If the test is acceptable, list the airflow rateat 50 Pa as calculated using the regressionresults on the Housing Unit Air-LeakageMeasurement Form. This number is usuallycalculated and output by the computer programprovided by the blower-door manufacturer.Calculate the natural infiltration rate in airchanges per hour as indicated on the form.Include the printout from each test with theHousing Unit Air-Leakage Measurement Form.

COMPLETION OF TESTING

Return ventilation controls, vents, andthermostats to their original settings. Make sureall space-heating, space-cooling, andwater-heating systems are operating correctly.Make sure all pilot lights are lighted. Closeinterior doors to restore the house to its originalstate.


MILITARY FAMILY HOUSING:HOUSING UNIT AIR-LEAKAGE MEASUREMENT FORM

IDENTIFICATION

Installation name: _____________________________________________Housing unit ID: ______________________________________________Housing unit address: __________________________________________Inspector: ____________________________________________________Inspection date: _______________________________________________

HOUSING UNIT PREPARATION

Housing unit prepared for testing? _____ (Y,N)Basement door: ______ (open, closed, NA)Preparation comments: _____________________________________________________________________________________________________________________________________________________________________Unusual sources of air leakage: __________________________________________________________________

HOUSE DATA

Climate zone Height Wind shieldingIntentionally conditioned

house volume (ft3)

Description

Correction factor C = H = S =

Climate zone: See Fig. C.1 for zone identification. Zone 1 (C=15.5), zone 2 (C=18.5), zone 3 (C-21.5), and zone 4 (C-24.5).Height: one story (H=1.0), one-and-a-half story (H=0.9), two stories (H=0.8), and three stories (H=0.7).Wind shielding:

Well shielded (S=1.2): Urban areas with high buildings or sheltered areas. Buildings surrounded by trees, bermedearth, or higher terrain.

Normal (S=1.0): Buildings in a residential neighborhood or subdivision setting, with yard space betweenbuildings (80-90% of houses fall into this category).

Exposed (S=0.9) Buildings in an open setting with few buildings or trees around. Buildings on top of a highhill or ocean front, exposed to winds.

Intentionally conditioned house volume: An intentionally conditioned space is one with equipment and/or distribution outletsdesigned to maintain a desired temperature in the space. Gross interior floor area (includes internal storage closets, etc.) areused to calculate volumes rather than net areas as defined by the military. Floor heights used to calculate volume are floor tofloor, except for the top floor, which is floor to ceiling. Use an average height for cathedral ceilings.


MEASUREMENT DATA

Indoor temperature (°F) Outdoor temperature(°F)

Windcondition

High wind gusts?(Yes, No)

Start End

Wind condition: calm (0-5 mph), moderate (5-10 mph), or higher (greater than 10 mph).

Pressure station Fan pressure(Pa)

Fan openingconfiguration

Airflow rate(cfm)Goal (Pa) Actual (Pa)

60

50

40

30

20

intermediate

intermediate

ANALYSES

Airflow rate at 50 Pa: _____ CFM50 (from regression)

Natural air changes per hour: _____ ACH = (CFM50 × 60)/(Volume × C × H × S)


DAppendix

SPECIFICATION FOR VISUALINSPECTION OF ENVELOPE AIRLEAKAGE

Specification for Visual Inspection of EnvelopeAir Leakage

Visual inspection of envelope air leakagewill be performed in existing single-familyhousing units (detached or attached) that willretain a significant portion of the exteriorenvelope and current interior configuration. Thepurpose of this visual inspection is to identifymajor air-leakage locations such as atticbypasses and unblocked partition walls thatneed to be sealed during revitalization.

BACKGROUND

Infiltration control is based on minimizingthe loss of conditioned air through the buildingenvelope (floors, walls, and ceilings).Infiltration (and corresponding exfiltrations) iscaused by two weather-relatedphenomena—wind pressure and the stack effectfrom the temperature difference betweenindoors and outdoors. Leaks in buildingenvelopes contribute differently to infiltrationdepending on their location and the cause ofairflow through the building.

Wind pressure acts primarily on walls,windows, doors, sill plates, and band joists.Examples of typical and recurring walldeficiencies are shown in Fig. D.1.

The stack effect acts mainly on fireplaces;penetrations in basements, crawl spaces, andattics (plumbing, electrical service, and otherunsealed ceiling penetrations such as cannedlight fixtures and air distribution ducts); and“attic bypasses.” Attic bypasses are paths forconvective air flow through interior and exteriorwalls (see Fig. D.2). Preventing air leakage intothe lowest level of the building and out of thehighest level is the best method for eliminatingstack-driven infiltration.

Floor cavities of second-story overhangsand second-story floors over porches contributesignificantly to infiltration because they connectthe interior of the housing unit to the outside

and because they are affected by wind pressureand stack effect.

The stack effect typically contributes moresignificantly to building air leakage than thewind effect. Although sealing small cracks inwalls and around windows is necessary toreduce infiltration, caulking small cracks doesnot significantly reduce stack-driven infiltrationand is very labor intensive.

Other penetrations in building envelopescontribute little to naturally caused infiltrationbut respond primarily to occupant activities andHVAC equipment operation. These penetrationsinclude exhaust vents (kitchen and bath) and airdistribution system leaks. Inspection of airdistribution systems is covered underSect. 4.1.9, “Air Distribution System.”

INSPECTION PROCEDURE

Identify on the Infiltration InspectionChecklist the installation at which the unit islocated. Assign a unique identification numberto the housing unit, or use the identificationnumber previously assigned to the housing unitif an energy inspection was performed by theA/E or if the air-leakage rate was measured.Document the address of the inspected unit,inspector, and inspection date.

This procedure starts with the lowest levelof the building (basement or crawl space) andproceeds to the attic. Use a blower door todepressurize the unit to 20-30 Pa and a synthetic“smoke” source to promote leakage detectioninside the housing unit. Pressurize the unit to20-30 Pa to help identify leakage sites in thebasement and attic. Observations from theinspection shall be recorded on the InfiltrationInspection Checklist to document the type andlocation of the problems that need to be sealedduring revitalization. Leakage locations thatneed to be sealed must be documented withsufficient accuracy and detail so that a sealing

VISUAL INSPECTION OF ENVELOPE AIR LEAKAGE D-1

(a)

(b)

Fig. D.1. Wall penetrations under sinks ( a) and behind appliances ( b) open the interior of the housing unitto the outside, attic, crawl space, or basement through exterior and interior walls.

D-2 VISUAL INSPECTION OF ENVELOPE AIR LEAKAGE

(a) (b)

(c) (d)

Fig. D.2. Attic bypasses connect the interior of the housing unit to the attic but are usually not visiblefrom within the house. Chaseways for ducts, flues, and plumbing ( a); unblocked interior partition walls thatoften exist between bathrooms and often have plumbing pipes through them ( b); empty spaces built aroundand above closets that open up to the attic ( c); and pocket doors ( d) are typical and recur frequently in familyhousing.


contractor can locate the sites at a later date. Theinformation recorded on the InfiltrationInspection Checklist should be supplementedwith additional material (such as pictures,sketches, house layouts) as needed to providethis accuracy and detail.

Basement or Crawl Space

Air movement by the stack effect flowsfrom low, cool locations such as basements andcrawl spaces up through floor penetrations andaround the sill plate. Therefore, infiltrationinspection in the basement and crawl spacefocuses on identifying the leakage sites in andaround the floor separating the basement orcrawl space from the main living area to thehouse (the basement or crawl space ceiling) thatmust be repaired and eliminated byrevitalization.

Main Floors

Inspection of the main floors between thebasement, crawl space, or slab floor and the atticfocuses on penetrations in the building envelopeand interior walls that can allow air movementfrom wind and stack effects. For multilevelbuildings, all levels should be inspected forconditions that can contribute to infiltration andexfiltration. Multilevel housing units can havesubstantial leakage areas where the second storyfloor opens into the exterior wall.

Attic

Inspection in the attic focuses on the topfloor ceiling that forms the attic floor, becausethis surface is the final barrier for exfiltration ofair from the stack effect. Check especially forattic bypasses such as open partition walls,plumbing chaseways, around electricalopenings, and open floor joists in kneewallattics.

D-4 VISUAL INSPECTION OF ENVELOPE AIR LEAKAGE

INFILTRATION INSPECTION CHECKLIST

Housing unit ID:_______

Installation: Unit Address:

Date: Inspectors:

Inspection point Infiltration problem Location

BASEMENT/CRAWL SPACE

Floor penetrations—electrical service

Floor penetrations—plumbing service

Floor penetrations—air ducts

Sill plate

Floor penetration—general

MAIN FLOOR

Wall penetrations under sinks and appliances

Exterior doors

Interior walls

Exterior walls

Ceiling penetrations above recessed lightingfixtures

Attic hatch

Whole-house fan

ATTIC

Ceiling penetrations—electrical service

Ceiling penetrations—plumbing service

Ceiling penetrations—air ducts

Canned light fixtures

Ceiling penetrations—general

Unblocked interior partition walls

Unblocked exterior walls

Plumbing and duct chaseways


EAppendix

SPECIFICATION FOR MEASURINGDUCT AIR-LEAKAGE RATE

Specification for Measuring Duct Air-Leakage Rate

The air-leakage rate of the air distributionsystem in a new housing unit will be measuredto determine its airtightness followingconstruction. Similarly, in an existing unit, theair-leakage rate of the existing duct system willbe measured before revitalization if the systemwill be retained, or the air-leakage rate of a newduct system will be measured after revitalization.

PREPARATION FOR TESTING

Identify on the Duct Air-LeakageMeasurement Form the installation at which theunit is located. Assign a unique identificationnumber to the housing unit, or use theidentification number previously assigned to thehousing unit if an energy inspection wasperformed by the A/E or if a blower-doorinspection of the house was performed.Document the address of the inspected unit,inspector, and inspection date.

Prepare the duct system as follows forinspection testing:

• Turn off all air handler and exhaust fans.• Open all supply and return registers.• Turn off exhaust fans, dryers, and room air

conditioners in the housing unit.• Open all interior doors.• Remove filters from the air distribution

system.

Record on the Duct Air-LeakageMeasurement Form that the housing unit wasprepared for testing. Note any other special orunusual situations encountered in preparing thesystem for testing.

Keep all equipment at a temperature asclose to 70°F as possible while in transit andbring it into the house immediately upon arrival.Set up the equipment following themanufacturer’s instructions and as specifiedbelow:

• Install the fan at the largest return or supplyregister closest to the air handler, or at theair handler cabinet itself. Check for leaksaround the fan.

• Seal off all return and supply registers in thesystem, as well as other intentional openingssuch as combustion or ventilation inlets.

• Open an exterior door or window.• Open vents, access panels, or doors to crawl

spaces, attics, and garages containing ducts.• Install the hose measuring the duct pressure

in a duct far removed from the fan, out ofthe direct flow of air through the fan. If thefan is installed in a supply register, installthe hose in the return system. If the fan isinstalled in a return register, install the hosein the supply system.

• Set up the gauges inside the house and outof the direct flow of air through the fan.

• Connect all hoses making sure all hosefittings are tight. Trim or tighten hoses asnecessary.

• Cover the fan opening as recommended bythe manufacturer (using a “shower cap”provided by the manufacturer, plugging ortaping all holes with the orifice plate on, orsome other equivalent technique).

• Zero all the gauges.• Remove the fan opening cover.

Briefly walk through the house whilemaintaining a positive pressure in the ductsystem of 15–20 Pa to check for previouslyundetected operable openings in the ducts and toensure that the register seals are tight.

TEST PROCEDURE

A test entails measuring the air-flow raterequired to pressurize the duct system to 50 Pa.If a pressure of 50 Pa cannot be achieved, thenthe airflow rate needed to pressurize the ducts to25 Pa must be measured.

SPECIFICATION FOR MEASURING DUCT AIR-LEAKAGE RATE E-1

For measuring systems with orifice plates orother means of reducing the size of the fanopening (plugging holes in a cover plate, etc.),the configuration that provides the greatestaccuracy and is within the range recommendedby the manufacturer must be used.

Make the measurement at 50 Pa (or 25 Pa)in the following manner:

• Raise the duct pressure to about 5 Pa abovethe desired pressure.

• Lower the duct pressure to about 5 Pa belowthe desired pressure. Then slowly increasethe pressure until the desired pressure isreached. If the pressure is overshot, lowerthe pressure again to 5 Pa below the desiredpressure and repeat the process.

• Tap the gauges continuously while adjustingthe pressure up to the desired station, as thestored spring energy will cause the gaugeneedles to jump slightly.

• Set the gauge needle on the indicatedpressure stations, within 0.5 Pa.

• After waiting 30 seconds for the readings tostabilize, record the actual duct pressurereading, fan pressure, fan openingconfiguration, and fan flow rate reading onthe Duct Air-Leakage Measurement Form.When lining the gauge needle up with themarks on the gauge, read the gauge fromdirectly in front to avoid parallax. Alwaystake readings off the gauge with the lowestrange possible. For example, whenmeasuring a flow pressure of less than125 Pa, read from a gauge with a range of0–125 Pa rather than one with a range of0–750 Pa.

COMPLETION OF TESTING

Return ventilation controls, vents, andthermostats to their original settings. Make sureall space-heating and space-cooling systems areoperating correctly. Make sure all pilot lightsare lighted. Close interior and exterior doorsand/or exterior windows to restore the house toits original state.

E-2 SPECIFICATION FOR MEASURING DUCT AIR-LEAKAGE RATE

MILITARY FAMILY HOUSING:DUCT AIR-LEAKAGE MEASURMENT FORM

IDENTIFICATIONInstallation name: __________________________________________Housing unit ID: ___________________________________________Housing unit address: _______________________________________Inspector: _________________________________________________Inspection date: ____________________________________________

DUCT SYSTEM PREPARATIONDuct system prepared for testing? _____(Y,N)Preparation comments: ________________________________________________________________________________________________________________________________________________________

MEASUREMENT DATA

Duct pressure Fan pressure(Pa)

Fan openingconfiguration

Airflow rate(cfm)Goal (Pa) Actual (Pa)

50

25 (optional)

SPECIFICATION FOR MEASURING DUCT AIR-LEAKAGE RATE E-3

FAppendix

SPECIFICATION FOR INSPECTION OFDUCT AIR LEAKAGE

Specification for Inspection of Duct Air Leakage

A detailed inspection of the existing airdistribution system will be performed inexisting housing units that will retain thesystem. The purpose of this inspection is toevaluate the condition of the system relative tocontinued long-term use (verify that it iseconomical to retain the current system) and toidentify the location and type of major ductleaks that need to be sealed during revitalization.

The purposes of a visual inspection of theair distribution system are as follows:

• to evaluate the need to replace all or parts ofthe system because of general deteriorationof the system;

• to determine whether the localized damagethat is responsible for excessive ductleakage can be repaired;

• to determine whether improper materials orsupports are present; and

• to evaluate whether duct insulation isadequate for continued use of the system.

Inspection for leaks is based on visualobservation enhanced by depressurizing thehousing unit with a blower door (or pressurizingthe ducts with a fan) to allow detection of leaksthrough observation of airflow with a synthetic“smoke” source.

BACKGROUND

Supply System

Leaks in the supply ducts of the airdistribution system are important becauseconditioned air is directly lost through thembefore it can be delivered to the house. Also,dominant supply leakage can result indepressurization of a house, increasing theinfiltration rate of the house whenever thesystem operates.

Main supply ducts are often fabricated fromsheet metal or ductboard, with branches toindividual registers fabricated from the same or

a different material, such as flexduct. Leaks areoften caused by circumferential joints that areunsealed or that are initially sealed with onlyfabric duct tape, which deteriorates (seeFig. F.1). Joints also may be poorly sealed orunsealed at the junction between the heating andcooling system and the supply trunk.

Junction boxes are fabricated of sheet metalor ductboard to divide supply air into twoseparate branch flows at the end of a supplytrunk. Leaks at junction boxes can occur at theseams of the box if duct tape is the only sealant.Also, duct connections to the box can leak ifthey are unsealed or sealed only with fabric ducttape.

Connections at supply registers often leakbecause of a poor seal between the branchductwork and the connecting “boot.” Poor sealsbetween the connecting boot and the registeritself also contribute to leaks. Figure F.2 showsa leak that occurs when a connecting metal bootis incorrectly installed to the supply register.

Lack of a mechanical fastener oftencontributes to the formation of joint leaks. Amechanical fastener is especially needed toconnect flexduct to supply registers to ensure along-lasting seal. Plastic ties, especially if usedin a hot attic, can become loose and slip off theboot connection.

Connecting boots fabricated from ductboardmay have poor seals where they slip over thesupply register.

Return System

Leaks in return ducts are often morecommon than leaks in supply ducts. Returnleaks are important because they pull hot or coldair and pollutants into a house from attics andother unconditioned locations. Also, dominantreturn leakage can result in pressurization of ahouse, increasing the loss of conditioned airthrough leaks in the building envelope.

SPECIFICATION FOR INSPECTION OF DUCT AIR LEAKAGE F-1

(a) (b)

(d)(c)

Fig. F.1. Circumferential joints in ductwork often deteriorate and leak if they lack mechanical fastenersand were initially unsealed or sealed only with fabric tape.

F-2 SPECIFICATION FOR INSPECTION OF DUCT AIR LEAKAGE

The importance of return leakage was notrecognized in the past, general thinking beingthat return leaks were a way to provide “fresh”air to a house. Therefore, it has been commonpractice to downplay the importance ofconstructing airtight return systems. Unsealedcavities in the building structure—walls, floorjoists, stud bays—have often been used as partsof the return “ductwork.”

Return grills are common leak locationswhen gaps are left between the grill and thewall, ceiling, or floor to which it is mounted. Aircan be sucked into the return from the outside,attic, or other unconditioned spaces through thewall, ceiling, or floor cavity. Figure F.3 shows aleak to a wall cavity behind a wall-mounted grill.

Return ducts that connect the return grill tothe heating and cooling system are usuallyconstructed from duct materials such as sheet

metal and ductboard, or building cavities areoften used. Return ducts constructed fromtraditional duct materials are prone to the sameleaks described for supply ducts. A commonproblem is the connection of a return duct to theheating or cooling system or a junction box atthe unit (see Fig. F.4).

Building cavities used as part of the returnsystem are often leaky and are inappropriatesubstitutes for dedicated ducts. Examplesinclude panned floor joist cavities formed byattaching sheet metal between floor joists, studbay cavities formed by wall studs and drywall,and floor truss cavities formed within floortrusses. Joints and penetrations in these cavitiesare typically not sealed, allowing unconditionedair to be drawn into the return from all parts ofthe housing unit and the outside. These leakscan also allow return air to be drawn from

Fig.F.2. A sheet metal boot in a newly installed duct system is improperly installed, creating a 1/2-in. gapbetween the boot and the supply register.


(a)

(b)

Fig. F.3. A leak to a wall cavity located behind a wall-mounted grill ( a). The joints in theductwork behind the grill are also deteriorated and leaking ( b).


adjacent townhouse units, which increases theinfiltration rate in the adjacent housing unit.Connections between ducts and these buildingcavities frequently are not sealed, and theirfailure creates large leakage areas (see Fig.F.5).

Heating and cooling units located in agarage are frequently mounted on a plywoodbox that is a return plenum. Units that areinstalled in an interior closet often use the entirecloset as a return plenum or sit upon a returnplenum built using a raised floor and the closetwalls. These plenums and closets are often notsealed, allowing nonconditioned air to be drawninto the return system. Figure F.6 shows a returnplenum built in a closet with unfaced interiorwalls and penetrations for plumbing andelectrical lines that allow air to be drawn fromthe outside and attic.

Return plenums are frequently built behindthe return grill, formed by spaces between floorsor under stairwells. Again, unsealed walls andpenetrations serve as leakage sites, allowing air

to be drawn into the return from all connectedspaces in the house and outside.

Air Handlers

Leaks at air handlers are important becausethe positive (supply) and negative (return)pressures at this location are the highest in thesystem. Incorrectly matched equipment sectionsand poor installation (frequently caused by tightquarters) can produce large leakage sites (seeFig. F.7). Even small leakage areas such as“knockouts” for wiring and equipment lines andcracks between panels can represent significantleakage paths (see Fig. F.8).

Supports for Ductwork

Ductwork can be hung from floor joists incrawl spaces and basements, and from rooftrusses in attics. Metal straps or bands are usedto provide support for ductwork. If the supports

Fig. F.4. Use of duct tape rather than mechanical fasteners to secure the connection of a return duct to ajunction box at an attic-mounted evaporator allowed the joint to fail, forming a significant return leak.


Fig. F.5. The joint between a return duct and a building cavity used as a return duct was not sealed andmechanically fastened and, following failure, created a large leakage area.

Fig. F.6. Unfaced interior walls and unsealed penetrations for plumbing and electrical lines in this returnplenum allow unconditioned air to be drawn into the return from the attic or the outside.


are inadequate or fail, the duct can drop andopen a leak at joints adjacent to the failurelocation.

Duct Insulation

All supply and return ductwork inunconditioned spaces should be insulated orhave insulation equivalent to current ductinsulation standards, nominally a level of atleast R-6. Older metal duct systems often were

installed without any insulation, even whenlocated in unconditioned spaces such as attics,crawl spaces, and unheated basements.

INSPECTION PROCEDURE

Identify on the Duct Inspection Checklistthe installation at which the unit is located.Assign a unique identification number to thehousing unit, or use the identification numberpreviously assigned to the housing unit if an

Fig. F.7. An evaporator that is physically too large for and poorly mounted to the furnace created a largesupply leak. Metal-faced duct tape used to seal the leak had deteriorated.


energy inspection was performed by the A/E, ablower-door inspection of the house wasperformed, or the tightness of the ducts weremeasured. Document the address of theinspected unit, inspector, and inspection date.

Prepare a schematic plan of the airdistribution system relative to the floor plan ofthe unit. The plan shall indicate the followingmajor features: (1) location of the heating andcooling equipment; (2) location of supply ductsand junction boxes; (3) location of return

plenums and return ducts; and (4) location andtype of building cavities used in the ductsystem. The plan shall include attic, basement,and living-level schematics as needed. The planshall be used to indicate the location of anyrepairable leaks found during the inspection.

The following diagnostics shall beperformed to identify the location of repairableduct leaks:

Fig. F.8. An unsealed “knockout” for wiring and refrigerator lines and a poorly fitting panel on thisattic-mounted evaporator allow attic air to be drawn into the return system.


1. Prepare the house as follows for blower-doortesting:

• Close all windows and outside doors.• Close the damper and outside air supply

to the fireplace (if present).• Close and secure the attic access hatch.• Turn off all air handler and exhaust fans.• Open all supply and return registers (if

present).• Remove filters from the air distribution

system (if present).• Turn off all combustion appliances.• Close doors to unconditioned utility

closets or other unconditioned spaces.• Open all interior doors (except for

closets) so that all interior conditionedspace is connected, includingconditioned basements.

2. Install a blower door on the house followingthe manufacturer’s recommendations.

3. Depressurize the housing unit to 50 Pa. 4. Working on one register at a time, create a

temporary airtight barrier across the registeropening by placing a “pressure pan” overthe register or using temporary (masking orpainter’s) tape applied over the face of thegrill.

5. Place a pressure gauge near the register to betested, and level and zero the gauge.

6. Measure the pressure difference across thecover (the difference in pressure inside theduct relative to the house) by connecting thegauge to the pressure pan or inserting asmall probe through the duct cover. Recordthe pressure difference on the DuctInspection Checklist.

7. Remove the temporary barrier across theregister, and leave the register open.

8. Repeat steps 4-7 for each register in thehouse. Move in a clockwise rotation in eachroom if more than one register is present.

9. Depressurize the house to 25–30 Pa.10. Visually inspect the duct system for leakage

using a source of synthetic “smoke” to aidin detecting leaks. Document the location ofrepairable duct leaks on the Duct InspectionChecklist and the duct schematics. Indicatethe magnitude of the duct leak on the ductschematic using the following key:X—small leak, XX—medium leak, andXXX—large leak.

11. Turn off the blower door and return thehouse to its original condition.

The airtightness of the duct system shouldhave been previously measured following aseparate procedure. If the leakage rate of theducts is less than 150 cfm at 50 Pa, then fewrepairable duct leaks should be expected. Thepressure readings made in Step 6 help guide thevisual inspection to identify the primarylocations for duct leakage by identifying theleakiest ducts. The higher the pressuredifference, the greater the amount of ductleakage expected in that leg of the duct system.Pressure differences of less than 2 Pa indicatelittle duct leakage.

The following points shall be considered indetermining if a duct leak should be identifiedas repairable:

• Leaks closest to the air handler are

important as the pressure driving forces aregreatest at the air handler.

• Leaks in return ducts located in the samezone as combustion equipment shouldalmost always be sealed to prevent possiblebackdrafting of combustion appliances.


MILITARY FAMILY HOUSING:DUCT INSPECTION CHECKLIST

Housing unit ID: __________

Installation: Unit address:

Date: Inspectors:

Room Floorb

Duct pressure (Pa)a

CommentsSupplyc Returnc

Foyer

Living

Dining

Kitchen

Family

Bath No. 1

Master Bdrm.

Bath No. 2

Brdm. No. 2

Bdrm No. 3

Bdrm. No. 4

Bath No. 3

Hallway No. 1

Hallway No. 2

UtilityaWith unit depressurized to 50 Pa and duct sealed.bMain, 2nd, 3rd, basement.cIf more than one register, list data in clockwise rotation from main entrance to room.


DUCT INSPECTION CHECKLIST — SUPPLY LEAKS House ID:____________

Ductfunctiona

Ducttypeb

Ductlocationc

Joint seal/reinforcementd

Numberof leaks Leak locations

Leaksizee

Comments andrecommendationsf

aST—supply trunk; SB—supply branch; JB—junction box; SR—supply register; HU—HVAC unit.bDuct types: DB—ductboard, SM—sheet metal, FD—flexduct, X—other.cLocation: A—attic, B—basement, C—crawl space, G—garage, X—other.dJoint sealant/reinforcement for circumferential joints: M—mastic; MT—metal-faced tape; FT—fabric tape; MS—metal screws; MB—metal band; PB—plastic band; N—none.eLeak size: width and length of gap, inches. fCause of leak—damaged duct, deteriorated seal, unsealed penetration, other. Repair recommendation—replace duct, repair joints or penetrations.

DUCT INSPECTION CHECKLIST — RETURN LEAKS House ID:____________

Ductfunctiona

Ducttypeb

Ductlocationc

Joint seal/reinforcementd


Leaksizee


aRG—return grill; RD—return duct; RP—return plenum.bDuct types: DB—ductboard, SM—sheet metal, FD—flexduct, SR—sheetrock, X—other.cLocation: A—attic, B—basement, H—hallway, C—crawl space, G—garage, X—other.dJoint sealant/reinforcement for circumferential joints: M—mastic; MT—metal-faced tape; FT—fabric tape; MS—metal screws; MB—metal band;

PB—plastic band; N—none.eLeak size: width and length of gap, inches. fCause of leak—damaged duct, deteriorated seal, unsealed penetration, other. Repair recommendation—replace duct, repair joints.

DUCT INSPECTION CHECKLIST — BUILDING CAVITIES House ID:____________

Ductfunctiona

Cavitytypeb

Ductlocationc Joint seald


Leaksizee


aRD—return duct; RP—return plenum.bCavity types: SB—stud bay, FT—floor truss, PFT—panned floor truss, F—floor.cLocation: IW—interior wall, EW—exterior wall, B—basement, C—crawl space, G—garage, X—other.dJoint sealant: M—mastic; MT—metal-faced tape; FT—fabric tape; N—none.eLeak size: width and length of gap, inches. fCause of leak—damaged duct, deteriorated seal, unsealed penetration, other. Repair recommendation—replace duct, repair joints.

DUCT INSPECTION CHECKLIST — INSULATION AND SUPPORTS House ID:____________

Ductfunctiona

Ducttypeb

Ductlocationc

Insulationtyped

Insulationconditione

Ductsupportf

Supportfailureg Comments

aST—supply trunk, SB—supply branch, RD—return duct, RP—return plenum, JB—junction box.bDuct types: DB—ductboard, SM—sheet metal, FD—flexduct, X—other. cLocation: A—attic, CB—conditioned basement, UB—unconditioned basement, C—crawl space, G—garage, H—hallway, X—other.dBatt, R=___; Blanket, R=___; Ductboard, R=___; Flexduct, R=___; Other, R=___; Other, R=___; None.

eGood—no repair; Fair—minor repairs; Degraded—replace.fA—adequate support, I—inadequate support (>10 ft span).gL—loose attachment, B—broken support, N—none.

GAppendix

ENERGY ANALYSIS FORMS FORREVITALIZED HOUSING UNITS

Form G.1. General information

Installation name: ______________________________________________________________________________________________________________

Housing unit type ID: ___________________________________________________________________________________________________________

Person completing forms: ________________________________________________________________________________________________________

Affiliation: ___________________________________________________________________________________________________________________

Form G.2. Thermal boundary Housing Unit Type ID:________

Provide a sketch of the floor plan(s) and the sections of the unit being revitalized, indicating the location of the thermal boundary to be achievedfollowing revitalization.

Form G.3. Wood-frame wall insulation Housing Unit Type ID: _________

Annual energysavingsa

(MBtu/ft2 orkWh/ft2)

Fuel cost($/MBtu or

$/kWh)

Annual costsavings

$/ft2

Uniformpresent worth

factorb

Present value ofthe energy

savings($/ft2)

Insulationinstallation

costc

($/ft2)

Savings-toinvestment

ratiod

Simplepaybackperiodd(years)

A B C = A ⋅ B D E = C ⋅ D F G = E/F H = F/C

Stud cavity:

Heating

Cooling + +

Total

Exterior:

Heating

Cooling + +

TotalaAnnual energy savings are determined from Figs. 4.2 through 4.5 and are per square foot of wall area.bThe uniform present worth factor is based on a 25-year life. The factor for the U.S. average in 1995 is 23.83 for natural gas, 23.00 for fuel oil, and 18.69 for electricity.cThe A/E must determine the total cost of installing the wall insulation per square foot of wall area. This cost must include all expenses associated with the improvement,

although some expenses may be appropriately assigned to other renovation work. For example, the total cost associated with installing exterior insulation is limited to materialsand direct installation cost of the insulation alone if existing siding is already to be replaced as part of the revitalization. An important factor for the A/E to consider for cavity insulation is whether the interior or exterior finishes will already be removed as part of the revitalization, providing ready and low-cost access to the wall cavity.

dThe stud cavity or exterior wall insulation meets military cost-effective criteria if the savings-to-investment ratio is greater than or equal to 1.25 and the simple payback period is less than or equal to 10. Insulation should be installed in both locations if both meet the cost-effective criteria.

Form G.4. Masonry wall insulation Housing Unit Type ID: _________



Fuel cost($/MBtu or

$/kWh)

Annual costsavings($/ft2)


factorb

Presentvalue of the

energy savings($/ft2)


costc

($/ft2)

Savings-to-investment

ratiod

Simplepaybackperiodd

(years)

Net presentvalued

($/ft2)

A B C = A ⋅ B D E = C ⋅ D F G = E/F H = F/C I = E – F

R-5 interior insulation:

Heating

Cooling + +

Total

R-11 to R-15 interior insulation:

Heating

Cooling + +

Total

R-5 exterior insulation:

Heating

Cooling + +

Total

R-10 exterior insulation:

Heating

Cooling + +

TotalaAnnual energy savings are determined from Figs. 4.6 and 4.7 and are per square foot of wall area.bThe uniform present worth factor is based on a 25-year life. The factor for the U.S. average in 1995 is 23.83 for natural gas, 23.00 for fuel oil, and 18.69 for electricity.cThe A/E must determine the total cost of installing the wall insulation per square foot of wall area. This cost must include all expenses associated with the improvement,

lthough some expenses may be appropriately assigned to other renovation work. For example, the total cost associated with installing exterior insulation is limited to materials anddirect installation cost of the insulation if a new exterior (stucco) is already to be installed as part of the revitalization.

dThe wall insulation measures meet military cost-effective criteria if the savings-to-investment ratios are greater than or equal to 1.25 and the simple payback periods are lessthan or equal to 10. The measure with the highest net present value should be installed if more than one measure meets the cost-effective criteria.

Form G.5. Slab-on-grade perimeter insulation Housing Unit Type ID:_________


(MBtu/ft orkWh/ft)

Fuel cost($/MBtu or

$/kWh)

Annual costsavings($/ft)


factorb

Presentvalue of the

energy savings($/ft)


costc

($/ft)


ratiod


(years)


Heating

Cooling + +

TotalaAnnual energy savings are determined from Figs. 4.8 and 4.9 and are per foot of perimeter.bThe uniform present worth factor is based on a 25-year life. The factor for the U.S. average in 1995 is 23.83 for natural gas, 23.00 for fuel oil, and 18.69 for electricity.cThe A/E must determine the total cost of installing the slab insulation per linear foot of perimeter. This cost must include all expenses associated with the improvement,

although some expenses may be appropriately assigned to other renovation work. For example, the total cost for slab insulation would be limited to materials and direct installation cost of the insulation if excavation around the perimeter is needed as part of the revitalization to fix moisture problems.

dThe slab insulation is cost effective if the savings-to-investment ratio is greater than or equal to 1.25 and the simple payback period is less than or equal to 10.

Form G.7. Attic insulation Housing Unit Type ID:_________

Standardinsulation

levels

Annualenergy

savings ofcurrent

insulationlevelsa

Annualenergy

savings ofstandardinsulation

levelsa

Annualincremental

energysavingsa

Fuel cost($/MBtu

or$/kWh)

Annualcost

savings($/ft2)

Uniformpresentworthfactorb

Presentvalue of the

energysavings($/ft2)


costc

($/ft2)


ratiod


(years)

Net presentvalued

($/ft2)

A B C = B – A D E = C ⋅ D F G = E ⋅ F H I = G/H J = H/E K = G - H

R-11:

Heating

Cooling + +

Total

R-19:

Heating

Cooling + +

Total

R-30:

Heating

Cooling + +

Total

R-38:

Heating

Cooling + +

Total

R-49:

Heating

Cooling + +

Total

aAnnual energy savings are determined from Figs. 4.14 and 4.15. They are expressed in MBtu/ft2 or kWh/ft2 and are per square foot of attic area. bThe uniform present worth factor is based on a 25-year life. The factor for the U.S. average in 1995 is 23.83 for natural gas, 23.00 for fuel oil, and 18.69 for electricity.cThe A/E must determine the total cost of installing the incremental amounts of attic insulation per square foot of attic area to upgrade to the standard insulation levels. For example, the A/E must

determine the cost to add R-8 insulation to achieve a total of R-19 if the current level is R-11. This cost must include all costs associated with the improvement, such as attic ventilation improvement, soffit dams, and access hatches.

dThe incremental amounts of insulation meet military cost-effective criteria if the savings-to-investment ratio is greater than or equal to 1.25 and the simple payback period is less than or equal to 10. If more than one level of insulation meets the cost-effective criteria, the level with the highest net present value should be selected.

Form G.8. Windows Housing Unit Type ID: _________

Annual energysavings of the

existing windowa

(MBtu/ft2 or kWh/ft2)

Annual energysavings of the new

window typea


Annual energysavings



(MBtu/ft2)bNew window area

(ft2)

Total annual energysavings(MBtu)

A B C = B – A D E F = D ⋅ E

Heating

Cooling + +

TotalaAnnual energy savings are determined from Figs. 4.19 and 4.20 and are per square foot of window area. bConvert space-cooling savings from kWh to MBtu by multiplying by 0.003413.

Form G.9. Storm window Housing Unit Type ID: _________

Heatingand

coolingcosts


(MBtu/ft2

orkWh/ft2)

Fuel cost($/MBtu

or$/kWh)

Annualcost savings

($/ft2)


Present valueof the energy

savings($/ft2)

Storm windowinstallation

costc

($/ft2)


ratiod


(years)


Heating

Cooling + +

TotalaAnnual energy savings are determined from Figs. 4.20 and 4.21 and are per square foot of window area. bThe uniform present worth factor is based on a 25-year life. The factor for the U.S. average in 1995 is 23.83 for natural gas, 23.00 for fuel oil, and 18.69 for electricity.cThe A/E must determine the cost to purchase and install the storm windows per square foot of window area.dA storm window meets military cost-effective criteria if the savings-to-investment ratio is greater than or equal to 1.25 and the simple payback period is less than or

equal to 10.

Form G.10. Glass exterior doors Housing Unit Type ID:_________

Annual energysavings of current

doora


Annual energysavings of the new

door typea





(MBtu/ft2)bNew door area

(ft2)

Total annual energysavings(MBtu)

A B C = B – A D E F = D ⋅ E

Heating

Cooling + +

TotalaAnnual energy savings are determined from Figs. 4.19 and 4.20 and are per square foot of window area. bConvert space-cooling savings from kWh to MBtu by multiplying by 0.003413.

Form G.11. New high-efficiency equipment Housing Unit Type ID: _________

System

Incrementalannualenergy

savingsa

(MBtu/ft2

orkWh/ft2)

Floorarea(ft2)

Fuel cost($/MBtu

or$/kWh)

Annual costsavings

($)


Presentvalue of

the energysavings

($)

Incrementalcostc

($)


ratiod


(years)

A B C D = A ⋅ B ⋅ C E F = D ⋅ E G H = F/G I = G/D

Furnaceor boiler

Airconditioner

Heat pumpaEnergy savings are obtained from Figs. 4.23 through 4.25 and are per square foot of floor area of the housing unit.

The total electricity savings of a high-efficiency heat pump is the sum of the electricity savings for air conditioning (Fig. 4.24) and heating (Fig. 4.25):

Space-cooling electricity savings: _____________________ kWh/ft2

Space-heating electricity savings: _____________________ kWh/ft2

bThe 18-year uniform present worth factor for the U.S. average in 1995 is 17.53 for natural gas and 17.06 for fuel oil. The 15-year factor for electricity is 12.43.cThe A/E must determine the incremental cost of installing the high-efficiency units compared with the minimum-efficiency units. The incremental cost includes the

greater material costs for the higher-efficiency unit, as well as other considerations such as greater installation labor or need for a new flue (assuming an 80% AFUE unitwould not itself need a new flue or chimney liner).

dThe high-efficiency unit meets military cost-effective criteria compared with the minimum-efficiency unit if the savings-to-investment ratio is greater than or equal to1.25 and the simple payback period is less than or equal to 10.

Form G.12. Heating and cooling system replacements based on potential for energy savings Housing Unit Type ID: _________

System



Floor area(ft2)

Fuel cost($/MBtu or

$/kWh)

Annualcost

savings($)



savings($)

Installationcostc

($)


ratiod


(years)

Net presentvalued

($)

A B C D = A ⋅ B ⋅ C E F = D ⋅ E G H = F/G I = G/D J = F – G

Furnace and Boiler

80%AFUE

92%AFUE

Air Conditioner

10 SEER

12 SEER

Heat Pump

10 SEER6.8 HSPF

12 SEER7.5 HSPF

aEnergy savings are obtained from Figs. 4.26 through 4.28 and are per square foot of floor area of the housing unit. The total unit total electricity savings of a high-efficiency heat pump is the sum of the electricity savings for air conditioning (Fig. 4.27) and heating (Fig. 4.28):

Space-cooling electricity savings: __________________________ kWh/ft2

Space-heating electricity savings: __________________________ kWh/ft2

bThe 18-year uniform present worth factor for the U.S. average in 1995 is 17.53 for natural gas and 17.00 for fuel oil. The 15-year factor for electricity is 12.43.cThe A/E must determine the cost of installing the replacement units. This cost includes the cost of the unit, removal of the existing unit, installation labor, and other

considerations such as need for a new flue or chimney liner.dThe replacement units meet military cost-effective criteria if the savings-to-investment ratio is greater than or equal to 1.25 and the simple payback period is less than or

equal to 10. If both a minimum-efficiency and a high-efficiency replacement unit meet the cost-effective criteria, the unit with the highest net present value should be installed.

Form G.13. Intermittent ignition device and vent damper Housing Unit Type ID: _________

System


(MBtu)Fuel cost($/MBtu)

Annualcost

savings($)



savings($)

Installationcostc

($)


ratiod

Simplepaybackperiod(years)

Net presentvalue of theinvestmentd

($)

A B C = A ⋅ B D E = C ⋅ D F G = E/F H = F/C I = E – F

Intermittentignition device

Thermal ventdamper

Electric ventdamper

aEnergy savings are obtained from Figs. 4.29 through 4.31.bThe 18-year uniform present worth factor for the U.S. average in 1995 is 17.53 for natural gas and 17.06 for fuel oil. cThe A/E must determine the cost of installing the retrofit measures. This cost includes material and installation costs.dThe retrofit measures meet military cost-effective criteria if the savings-to-investment ratios are greater than or equal to 1.25 and the simple payback period is less than or

equal to 10. If both a thermal and an electric vent damper are economical, then select the damper with the highest net present value.

Form G.14. Water heater fuel conversion Housing Unit Type ID: _________

Annual energycosta

($)



cost($)

Conversion costc

($)


ratiod


(years)

A B C = A ⋅ B D E = C/D F = D/A

Other fuel: ________

Cost-effective fuele: _________ – –

Difference aAnnual energy cost is determined from Figs. 4.34 and 4.35.bThe uniform present worth factor is based on a 12-year life. The factor for the U.S. average in 1995 is 11.81 for natural gas and 10.24 for electricity.cThe A/E must determine the total cost of conversion. This cost includes flue installation or removal, the gas hookup (possibly including the service entrance piping and piping

to the water heater) or disconnect, and the incremental cost (if any) between minimum-efficiency gas and electric units.dConversion to a different hot water heater meets military cost-effective criteria if the savings-to-investment ratio is greater than or equal to 1.25 and the simple payback period

is less than or equal to 10.eCost-effective fuel is determined from Fig. 4.33.

Form G.15. High-efficiency water heater selection Housing Unit Type ID: _________

Annual energycosta

($)



consumption($)

Installation costc

($)


ratiod


(years)

A B C = A ⋅ B D E = C/D F = D/A

Minimum-efficiency unit

High-efficiencyunit – –

DifferenceaAnnual energy cost is determined from Figs. 4.34 and 4.35.bThe uniform present worth factor is based on a 12-year life. The factor for the U.S. average in 1995 is 11.81 for natural gas, 11.56 for fuel oil, and 10.24 for

electricity.dThe A/E must determine the incremental cost associated with the high-efficiency water heater compared with the minimum-efficiency unit.eThe high-efficiency water heater meets military cost-effective criteria if the savings-to-investment ratio is greater than or equal to 1.25 and the simple payback period is

less than or equal to 10.

Form G.16. Lighting strategy Housing Unit Type ID: _________

Space PurposeDaily

use (hours) LocationFixture

typeLamptype Control

Form G.17. Summary of revitalization impact on housing unit energy performance Housing Unit Type ID: _________

Installation name: CAPS energy budget: kBtu/ft2

Existing intentionally conditioned area: ft2 Estimated current energy consumption intensity: kBtu/ft2

Impact item

Envelope and equipment specification Estimated annual energy savingsfrom revitalizationa

(MBtu)Existing unit Revitalized unit

Insulation

Wall R: R:

Foundation R: R:

Attic or ceiling R: R:

Infiltration cfm50

Windows and doors

Windows

Storm windows

Exterior glass doors

Heating and cooling system

Heating equipment AFUE: _______________HSPF: _______________

AFUE: _______________HSPF: _______________

Cooling equipment SEER: SEER:

Intermittent ignition device

Vent damper

Distribution system cfm50

Domestic water heating Eff.: _______________Fuel: _______________

Eff.: _______________Fuel: _______________

TotalaMultiply electricity savings (kWh) by 0.003413 to convert to MBtu.

HAppendix

DESIGN WEATHER DATA FORINSTALLATIONS IN THE UNITED STATES

Table H.1. Weather data for U.S. Air Force bases

State Base CityHeating-degree

daysCooling-degree

days

Alabama Gunter Gunter 2153 2487

Maxwell Montgomery 2153 2489

Arizona Davis-Monthan Tuscon 1574 2985

Luke Glendale 1410 3601

Williams Chandler 1535 3503

Arkansas Baker Blythville 3760 1789

Little Rock Little Rock 3354 2034

California Beale Marysville 2835 1525

Castle Merced 2590 1566

Edwards Lancaster 3077 1829

George Victorville 2885 1877

Los Angeles Los Angeles 1819 985

March Riverside 2162 1343

Mather Sacramento 2600 1303

McClellan Sacramento 2566 1406

Norton San Bernardino 1978 1499

Travis Fairfield 2725 831

Vandenberg Lompoc 3451 66

Colorado Lowry Denver 5978 625

Peterson Colorado Springs 6473 481

USAF Acadamy Colorado Springs 6973 100

Delaware Dover Dover 4756 1115

Florida Eglin Valparaiso 1658 2620

Homestead Homestead 218 3906

Hurlburt Ft. Walton Beach 1782 2370

MacDill Tampa 560 3493

Patrick Cocoa Beach 452 3405

Tyndall Panama City 1413 2737

Georgia Moody Valdosta 1549 2716

Robins Macon 2244 2276

Hawaii Hickam Honolulu 0 4221

Wheeler 8 2821

Idaho Mountain Home Mountain Home 5732 907

DESIGN WEATHER DATA FOR INSTALLATIONS IN THE U.S. H-1

Table H.1 (continued)


daysCooling-degree

days

Illinois Chanute Rantoul 5966 1052

Scott Belleville 4855 1421

Indiana Grissom Bunker Hill 6278 837

Kansas McConnell Wichita 4695 1406

Louisiana Barksdale Bassier City 2337 2451

England Alexandria 1964 2606

Maine Loring Limestone 9500 152

Maryland Andrews Camp Springs 4551 1237

Massachusetts Hanscom Bedford 6474 591

Michigan K. I. Sawyer Marquette 9498 198

Wurtsmith Oscoda 7929 363

Minnesota Duluth Duluth 9757 176

Mississippi Columbus Columbus 2890 2039

Keesler Biloxi 1549 2793

Missouri Whiteman Knob Noster 5012 1410

Montana Malmstrom Great Falls 7671 370

Nebraska Offutt Omaha 6213 1157

Nevada Nellis Las Vegas 2377 3089

New Hampshire Pease Portsmouth 6846 481

New Jersey McGuire Wrightson 5139 983

New Mexico Cannon Clovis 4046 1297

Holloman Alamogordo 3223 1870

Kirtland Albuquerque 4337 1394

New York Griffiss Rome 7331 472

Plattsburgh Plattsburgh 8044 461

North Carolina Pope Fayetville 3122 1828

Seymour Johnson Goldsboro 3124 1769

North Dakota Grand Forks Grand Forks 9963 400

Minot Minot 9625 398

Ohio Wright-Patterson Dayton 5455 1036

Oklahoma Altus Altus 3346 2347

Tinker Oklahoma City 3588 2068

Vance Enid 3971 2088

H-2 DESIGN WEATHER DATA FOR INSTALLATIONS IN THE U.S.



daysCooling-degree

days

South Carolina Charleston Charleston 2146 2078

Myrtle Beach Myrtle Beach 2696 1823

Shaw Sumter 2453 2160

South Dakota Ellsworth Rapid City 7049 738

Tennessee Arnold Tullahoma 3883 1212

Texas Bergstrom Austin 1712 3078

Brooks San Antonio 1272 3339

Carswell Ft. Worth 2301 2858

Dyess Abilene 2682 2500

Goodfellow San Angelo 2240 2702

Kelly San Antonio 1520 3190

Lackland San Antonio 1520 3190

Laughlin Del Rio 1542 3281

Randolph San Antonio 1713 2995

Reese Lubbock 3453 1738

Sheppard Wichita Falls 2904 2606

Utah Hill Ogden 6081 920

Virginia Langley Hampton 3623 1539

Washington Fairchild Spokane 6790 416

McChord Tacoma 5287 94

Washington, D.C. Bolling Washington, D.C. 4153 1517

Wyoming F. E. Warren Cheyenne 7255 327


Table H.2. Infiltration degree-days for U.S. cities

City and stateInfiltration degree-days

(°F-days)

Annette, AKBethel, AKBig Delta, AKFairbanks, AKGulkana, AKHomer, AKJuneau, AKKing Salmon, AKMcGrath, AKNome, AKYakutat, AK

836919,86119,26316,60915,48310,38210,17515,23316,74018,36410,038

Birmingham, ALMobile, ALMontgomery, AL

446844804463

Fort Smith, ARLittle Rock, AR

60086023

Phoenix, AZTuscon, AZWinslow, AZYuma, AZ

3305309354434264

Bakersfield, CAFresno, CALos Angeles, CAMount Shasta, CAOakland, CARed Bluff, CASan Diego, CASan Francisco, CASanta Maria, CA

260031031698580129433795112836922801

Colorado Spring, CODenver, COGrand Junction, COPueblo, CO

7793680660736229

Hartford, CT 7881

Wilmington, DE 6884



City and StateInfiltration degree-days

(°F-days)

Apalachicola, FLDaytona, FLJacksonville, FLMiami, FLOrlando, FLTallahassee, FLTampa, FLW. Palm Beach, FL

46704266450159064593363346295910

Augusta, GAAtlanta, GAMacon, GASavannah, GA

4618490644534387

Hilo, HIHonolulu, HILihue, HI

176736263200

Des Moines, IASioux City, IA

914910,560

Boise, IDLewiston, ID

67465643

Chicago, ILMoline, ILSpringfield, IL

878186348382

Evansville, INFort Wayne, INIndianapolis, INSouth Bend, IN

6326842779138257

Dodge City, KSGoodland, KSTopeka, KS

902593668214

Lexington, KYLouisville, KY

64936574

Baton Rouge, LALake Charles, LANew Orleans, LAShreveport, LA

4692532446525347

Boston, MA 8472

Baltimore, MD 6570




(°F-days)

Caribou, MEPortland, ME

12,5508585

Alpena, MIDetroit, MIFlint, MIGrand Rapids, MISault Ste. Marie, MI

8805862489368793

11,313

Duluth, MNInternational Falls, MNMinneapolis, MNRochester, MN

12,51513,26610,86011,663

Columbia, MOKansas City, MOSpringfield, MOSt. Louis, MO

7507748175397793

Jackson, MSMeridian, MS

48964399

Billings, MTGlasgow, MTGreat Falls, MTHelena, MTMiles City, MTMissoula, MT

10,37611,59710,878

891599597577

Asheville, NCCape Hatteras, NCCharlotte, NCGreensboro, NCRaleigh, NC

54215525453949905103

Bismarck, NDFargo, ND

12,41913,896

Grand Island, NENorth Platte, NEOmaha, NEScottsbluff, NE

10,175920089509374

Concord, NH 8240

Newark, NJ 6799




(°F-days)

Albuquerque, NMClayton, NMRoswell, NM

485472064989

Elko, NVEly, NVLas Vegas, NVReno, NVWinnemucca, NV

71479432352459296901

Albany, NYBuffalo, NYNew York, NYRochester, NYSyracuse, NY

81859840751894379047

Akron, OHCincinnatti, OHCleveland, OHColumbus, OHDayton, OHToledo, OHYoungstown, OH

8118675685797328768185708688

Oklahoma City, OKTulsa, OK

77617665

Astoria, ORMedford, ORPortland, ORSalem, OR

5025472148605027

Allentown, PAAvoca, PAErie, PAHarrisburg, PAPhiladelphia, PAPittsburgh, PA

784176808843647069177462

Providence, RI 7679

Charleston, SCColumbia, SC

50724635

Huron, SDRapid City, SDSioux Falls, SD

12,60510,14311,326




(°F-days)

Chattanooga, TNKnoxville, TNMemphis, TNNashville, TN

5102504259315607

Abilene, TXAmarillo, TXAustin, TXBrownsville, TXCorpus Christi, TXDel Rio, TXEl Paso, TXFort Worth, TXHouston, TXLubbock, TXMidland Odessa, TXPort Authur, TXSan Angelo, TXSan Antonio, TXWaco, TXWitchita Falls, TX

6655727456528193812855243633638361896150495754495084513869167358

Salt Lake City, UT 6632

Norfolk, VARichmond, VARoanoke, VA

582951195552

Burlington, VT 9319

Olympia, WASeattle, WASpokane, WATakima, WA

5299581178235997

Green Bay, WILa Crosse, WIMadison, WIMilwaukee, WI

10,434922097859855

Charleston, WV 5294


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