tecw students 11 0422
TRANSCRIPT
The Energy Code WorkshopStudents
Welcome
www.tecworkshop.com
Video – TECW Intro
Objectives
OJECTIVE: To raise awareness of building energy codes throughout Arizona based on the 2009 IECC
What it’s not
The Energy Code Workshop is NOT about…
Advocacy
Green Rating Systems
Creating experts
Enforcement
Environment
Policy
LEED
Eco
Compliance
The Energy Code Workshop is…
What is it?
• Market driven• CEU approved• Certifying 20 Approved Trainers - Statewide• Training1200 individuals prior to June 10, 2011• Raising energy code awareness throughout Arizona
Continuing Education
20 Approved Trainers
“U.S. new home sales hit record low, outlook
gloomy”
March 23, 2011
Market DrivenCurrent Market Trends
“New home sales tumble to record
low”
March 23, 2011
“Office vacancy rates in Valley hit
record”Oct 15, 2009
Code Adoption in Arizona
107 Municipalities in Arizona
35 have adopted a code (2000-2006)
4 have adopted the IECC 2009
Only 1 ICC Instructor in Arizona
Energy Codes Trends
Source: Pew Center on Global Climate Change
U.S. Energy Use
DOE and Federal Support includes:
1. Participation in development andupdating of codes andstandards
2. Provision of financial andtechnical assistance toadopt, implement, andenforce codes and standards.
1. Provide compliancetools.
2. Provide information andresources, complianceproducts, training, and energycode related news.
DOE Support
Reduced energy consumption by approximately 0.5-quadrillion Btu per year by 2015,and 3.5-quadrillionBtu per yearby 2030.
Rising cost savingsmore than $4 billion
per year back inhomeowners’ pockets by 2015, a figure that could
rise to over $30 billion per year by 2030
Reduced CO2 emissionsby roughly 3 percent in terms of the projected
national CO2 emissions in 2030.
Code Benefits
Energy Conservation Codes Are…
• Minimum requirements for energy-efficient design and construction:– Residential and commercial– New and renovations
• A component of a complete set of building regulations:– Structural, plumbing, electrical, energy, and
more
• Energy-efficiency baselines for:– Building envelope, mechanical equipment,
service water heating and lighting systems
• Effectively conserves energy• Minimizes increases in construction costs• Allows the use of new materials, products,
or methods of construction• Eliminates preferential treatment for
particular industries or types or classes of materials, products or methods of construction
Intent of IECC
• Code Development– Reaching consensus on the details
• Code Adoption– Not automatic in many states
• Code Compliance– Learning to design using new standards and
techniques– Implementing new requirements at the jobsite– Providing staff and resources to plan, review,
and inspect
Code Challenges
International Energy Conservation Code
ASHRAE Standard 90.1
State and Locally Adopted Codes
Building Energy Codes
Energy Codes & Standards History of U.S. Residential Energy Code
Baseline: IECC and ASHRAE 90.1
Both IECC and ASHRAE 90.1 apply, ASHRAE 90.1 likely used
Both IECC and ASHRAE 90.1 apply, either used to comply
IECC applies
Going Above and Beyond Code
SpawGlass Construction Corporate Headquarters, Houston, TXASHRAE Advanced Energy Design Guide for Small Office Buildings, 2008
• Building Envelope
• Mechanical
• Service Water Heating
• Lighting
• Electrical Power
For both residential and commercial:
What Do Building Energy Codes and Standards Cover?
Structure of IECC
Chapter 1 AdministrativeChapter 2 DefinitionsChapter 3 Climate ZonesChapter 4 Residential Energy EfficiencyChapter 5 Commercial Energy EfficiencyChapter 6 Referenced Standards
IECC covers one- and two-family residences ≤ 3 stories
All buildings that are not “residential” by definition are “commercial”
Includes additions, alterations, renovations and repairs
101.4
Scope
Existing buildings (Section 101.4.1)
– Electrical power, lighting, and mechanical systems still apply
Buildings designated as historic (Section 101.4.2)
AdministrativeExempted Buildings
101.4.1, 101.4.2, 101.5.2
Code applies to any new construction
Unaltered portion(s) do not need to comply
Additions can comply alone or in combination with existing building
AdministrativeAdditions, Alterations, Renovations, Repairs
101.4
Treat as a stand-alone “building” Additions must meet the prescriptive
requirements in Table 402.1.1 (or U-factor or total UA alternatives)
AdministrativeAdditions
101.4.3
Exceptions Storm windows over existing fenestration Glass-only replacements Exposed, existing ceiling, wall or floor cavities if already filled with
insulation Where existing roof, wall or floor cavity isn’t exposed Reroofing for roofs where neither sheathing nor insulation exposed
– Insulate above or below the sheathing
• Roofs without insulation in the cavity
• Sheathing or insulation is exposed
Lighting alterations if:
– <50% of luminaries in a space are replaced
– Only bulbs and ballasts within existing luminaries are replaced (provided installed interior lighting power isn’t increased)
Any non-conditioned space that is altered to become conditioned space is required to be brought into full compliance with code.
AdministrativeAdditions, Alterations, Renovations, Repairs
101.4.3
Any non-conditioned space that is altered to become conditioned space shall be required to be brought into full compliance with this code
Examples: Converting a garage to a family
room Heating an unfinished basement
AdministrativeSpace Conditioning
101.4.5
Treat the residential occupancy under the applicable residential code
Treat the commercial occupancy under the commercial code
AdministrativeMixed Use Buildings
101.4.6
Very low energy use buildings (<3.4 Btu/h-ft2 or 1 watt/ft2) (Section 101.5.2)
Buildings (or portions of) that are neither heated nor cooled (Section 101.5.2)
AdministrativeExempted Buildings – Thermal Envelope
101.4.1, 101.4.2, 101.5.2
Structure of IECC
Chapter 1 AdministrativeChapter 2 DefinitionsChapter 3 Climate ZonesChapter 4 Residential Energy EfficiencyChapter 5 Commercial Energy EfficiencyChapter 6 Referenced Standards
Definitions Examples
Air barrier – Materials “assembled and joined together”, a single material or combination of materials, i.e. sealants, acting as a system.
Basement wall – “…enclosing conditioned space.” If unconditioned, is classified as a crawl space.
Fenestration – includes skylights & doors.U-value/R-value – Reciprocal values between transmittance
and resistance. Note that U-value includes air films. U-value is calculated through a “component or assembly”, and R-value through a “body”. 402.1.2 (components) and 402.1.3 (assembly) make the difference more clear. C-factor is very similar to U-value (surface to surface instead of air to air) and is used in SHGC calculations.
High-efficacy lamps – minimum lumens/watt requirementLabeled and Listed – borrowed from the IBC
Structure of IECC
Chapter 1 AdministrativeChapter 2 DefinitionsChapter 3 Climate ZonesChapter 4 Residential Energy EfficiencyChapter 5 Commercial Energy EfficiencyChapter 6 Referenced Standards
General Requirements Climate Zones
Figure 301.1
CDD50°F – Interior base temperature = 50°F for CDD HDD65°F – Interior base temperature = 65°F for HDD
General Requirements Climate Zones
Table 301.3(2)
General Requirements Arizona Climate Zones
• National Fenestration Rating Council (NFRC) provide a thermal rating for windows and skylights in the U.S.
Additional Provision: Windows
Thermal Envelope Basics
Thermal Envelope Basics Heat Transfer
Heat always flows from warmer to cooler substances. Heat is transferred by three means:
ConductionRadiationConvection
Conduction is the transfer of vibrating energy (heat) between adjacent molecules. Transfer is always from warmer to cooler substances. Transfer is independent of gravity and can occur in any direction (up, down, sideways).
Thermal Envelope Basics Heat Transfer: Conduction
Radiation is the transfer of heat (molecular vibrating energy) by electro-magnetic waves. Transfer is always from warmer to cooler substances. Transfer is independent of gravity and can occur in any direction (up, down, sideways).
Surfaces must have a “line of sight” to each other for the transfer of energy.
Thermal Envelope Basics Heat Transfer: Radiation
Convection is the transfer of heat (molecular vibrating energy) by a moving fluid medium (water, air). Transfer is always from warmer to cooler substances. Energy is transferred by the physical relocation of molecules as the fluid moves.
Thermal Envelope Basics Heat Transfer: Convection
Thermal conductivity (k) Thermal conductance (C)
Thermal Envelope Basics Heat Transfer: Conduction
• Thermal resistance (R, or R-value) is the reciprocal of thermal conductance.
• The units are hour-square foot-°F per Btu OR (hr*ft2*°F)/ (Btu)
• The greater the R-value, the greater the thermal insulation.
Thermal Envelope Basics Heat Transfer: Resistance
• Infrared, both near & far are invisible to the eye.
• Far IR is emitted from warm surfaces.
• Radiation in either of these spectrums that is transmitted or reflected retains similar wavelength characteristics.
• Radiation that is absorbed is converted to heat which is then conducted, convected, or reradiated.
• This re-radiation only occurs in far IR spectrum.
Thermal Envelope Basics Heat Transfer: Radiation
Reflection – retains similar wavelength propertiesas the originating radiative energy Absorption – converted to heat and is then conducted, convected, or reradiated Transmission – retains similar wavelength properties Heat Loss – to the exterior and to the interior
Incident Radiation
When adding reflection, absorption and transmission percentages, the value must equal 1.0.1
Thermal Envelope Basics Heat Transfer: Radiation
• Emissivity is the measure of the ability of a surface to emit radiation at a given surface temperature
• The range of unitless values is 0.0 (no emittance possible) to 1.0 (ideal maximum – a “black body”).
• At any given temperature, a surface’s emissivity is exactly equal to its absorptance
Thermal Envelope Basics Heat Transfer: Emissivity
Natural Convection
Thermal Envelope Basics Heat Transfer: Convection
Forced Convection
Walls Roof or Floor
Thermal Envelope Basics Heat Transfer
Thermal Envelope Basics Heat Transfer
Chapter 4Residential Energy Efficiency
Chapter 1 AdministrativeChapter 2 DefinitionsChapter 3 Climate ZonesChapter 4 Residential Energy EfficiencyChapter 5 Commercial Energy EfficiencyChapter 6 Referenced Standards
Structure of IECC
ResidentialRelationship Between IRC & IECC
IECC addresses only energy
IRC addresses all topics (structural, plumbing, etc.)
• Allows builder to carry only one code book• Chapter 11 covers energy efficiency
IRC allows compliance with IECC as an alternative to Chapter 11
IECC addresses both residential and commercial; IRC addresses subset of residential, detached one- and two-family dwellings and townhouses 3 stories or fewer
Energy requirements in IRC and IECC almost identical
• IRC requires 0.35 SHGC in Climate Zones 1-3; IECC requires 0.30
• IRC has less stringent foundation requirements in northern zones
• Other minor differences
IECC TerminologyPrescriptive
• Required, but can be lessened or eliminated in trade for compensating improvements elsewhere
Mandatory• Required and cannot be traded down, even in the simulated
performance path
Some elements have “hard limits”aka, “trade-off limits”a prescriptive requirement that can only be traded
so farperformance requirements can only be traded so far
Residential Scope – Overview of Structure
402, 403
Focus is on building envelope– Ceilings, walls, windows, floors, foundations– Sets insulation and fenestration levels, and solar heat
gain coefficients– Infiltration control - caulk and seal to prevent air leaks
Ducts – seal and insulate Limited space heating, air conditioning, and
water heating requirements– Federal law sets most equipment efficiency
requirements, not the I-codes No appliance requirements Lighting equipment – 50% of lamps to be high-
efficacy lamps
Residential Overview of Residential Code Requirements
Chapter 4
Permanently posted on or in the electrical distribution panel
Don’t cover or obstruct the visibility of other required labels
Includes the following:– R-values of insulation installed for
the thermal building envelope, including ducts outside conditioned spaces
– U-factors for fenestration– SHGC for fenestration– HVAC efficiencies and types– Water heating equipment
Residential Compliance Certificate
401.3
Mandatory Requirements (apply everywhere): Duct insulation and sealing Infiltration control HVAC controls Piping Insulation Equipment sizing Dampers
Climate-Specific Requirements: Foundations
• Basements• Slabs• Crawlspaces
Above grade walls Skylights, windows, and doors Roofs Solar Heat Gain Coefficient in warm climates
Residential Scope Overview of Structure
Chapter 4
59
Mandatory Provisions
Prescriptive
Envelope Section 402
Envelope ProvisionsSection 402.2, 402.3.3 thru 402.3.6 & 402.5 (As Applies)
Simulated Performance Section 405Insulation
RequirementsFenestration
Section 403.2.1 & 404.1
Table 402.1.3
Section 402.3.1 & 402.3.2 (Trade-Off)
Section 402.1.1 & 402.1.2 (Tabular)
Section 402.1.3 & 402.1.4 (Trade-Off)
Project Complies
OR OR
Residential Scope Compliance Pathways
Thermal Envelope
CLIMATE ZONE
FENESTRATION U-FACTORb
SKYLIGHTb U-FACTOR
GLAZED FENESTRATIONb,e
SHGC
CEILING R-VALUE
WOOD FRAME WALL
R-VALUE
MASS WALL
R-VALUEi
FLOOR R-
VALUE
BASEMENTc WALL
R-VALUE
SLABd R-VALUE & DEPTH
CRAWL SPACEc
WALL R-VALUE
1 1.20 0.75 0.30 30 13 3 / 4 13 0 0 0 2 0.65j 0.75 0.30 30 13 4 / 6 13 0 0 0 3 0.50j 0.65 0.30 30 13 5 / 8 19 5 / 13f 0 5 / 13
4 except Marine
0.35 0.60 NR 38 13 5 / 10 19 10 / 13 10, 2ft 10 / 13
5 and Marine 4
0.35 0.60 NR 38 20 or 13+5h 13 / 17 30g 10 / 13 10, 2 ft 10 / 13
6 0.35 0.60 NR 49 20 or 13+5h 15 / 19 30g 15 / 19 10, 4 ft 10 / 13 7 and 8 0.35 0.60 NR 49 21 19 / 21 38g 15 / 19 10, 4 ft 10 / 13
Table 402.1.1Insulation and Fenestration Requirements by Component
Note: Most of the tables have footnotes which can also contain requirements.
Residential Envelope Insulation & Fenestration by Climate Zone
Table 402.1.1
a. R-values are minimums, U-factors and SHGC are maximums, R-19 batts compressed into a nominal 2 x 6 framing cavity such that the R-value is reduced by R-1 or more shall be marked with the compressed batt R-value in addition to the full thickness R-value.b. The fenestration U-factor column excludes skylights. The SHGC column applies to all glazed fenestration.c. “15/19” means R-15 continuous insulated sheathing on the interior or exterior of the home or R-19 cavity insulation at the interior of the basement wall. “15/19” shall be permitted to be met with R-13 cavity insulation on the interior of the basement wall plus R-5 continuous insulated sheathing on the interior or exterior of the home. “10/13” means R-10 continuous insulated sheathing on the interior or exterior of the home or R-13 cavity insulation at the interior of the basement wall.d. R-5 shall be added to the required slab edge R-values for heated slabs. Insulation depth shall be the depth of the footing or 2 feet, whichever is less in Zones 1 through 3 for heated slabs.e. There are no SHGC requirements in the Marine Zone.f. Basement wall insulation is not required in warm-humid locations as defined by Figure 301.1 and Table 301.1.g. Or insulation sufficient to fill the framing cavity, R-19 minimum.h. “13+5” means R-13 cavity insulation plus R-5 insulated sheathing. If structural sheathing covers 25 percent or less of the exterior, insulating sheathing is not required where structural sheathing is used. If structural sheathing covers more than 25 percent of exterior, structural sheathing shall be supplemented with insulated sheathing of at least R-2.i. The second R-value applies when more than half the insulation is on the interior of the mass wall.j. For impact rated fenestration complying with Section R301.2.1.2 of the IRC or Section 1608.1.2 of the IBC, maximum U-factor shall be 0.75 in Zone 2 and 0.65 in Zone 3.
Residential Envelope Insulation & Fenestration by Climate Zone
Table 402.1.1
Conditioned Space
attic
Residential EnvelopeSpecific Requirements
Building Envelope consists of:FloorsSlabsCrawlspacesWalls
• Above grade• Below grade• Mass walls
FenestrationCeilings
Exception: If framing members are too small to accommodate R-30, insulation that fills the framing cavity, not less than R-19, complies
Residential EnvelopeFloors Over Unconditioned Space
Table 402.1.1
Unconditioned space includes unheated basement, vented crawlspace, or outdoor air
Insulation must maintain permanent contact with underside of subfloor
Climate Zones R-Value1-2 13
3-4ab 194c-6 307-8 38
**
* Exception
Climate Zones 4c-8 R-19 permitted if cavity completely filled
Residential EnvelopeFloors Over Unconditioned Space
402.2.8
R-19 + 6 in 2x6R-19 +12 in 2x8 or 2x10
R-19
R-19, 2x6R-19 + 6 in 2x8 or 2x10
R-13
Steel Joist Floor
R-13 +10 or R-19 +9 or R-25 +8R-21
R-13 + 9 or R-19 +8 or R-25 +7R-19
R-13 + 5 or R-15 +4, or R-21 +3 or R-0+10
R-13
Steel Framed Wall
R-49 2x4, or 2x6, or 2x8, or 2x10R-38
R-38 in 2x4, or 2x6, or 2x8R-49 any framing
R-30
Steel Joist Ceilings
R-38 + 5R-49
R-49 or R-38 + 3R-38
R-38 or R-30 + 3 or R-26 + 5R-30
Steel Truss Ceilings
Cold-Formed Steel Equivalent R-valueWood Frame R-valueTable 402.2.5
Steel-Frame Ceiling, Wall and Floor Insulation (R-Value)
Table keys on the wood-frame requirement for the corresponding building component
“R-X + Y” means R-X cavity plus R-Y continuous
Exception: In climate zones 1 and 2, the continuous R-value can be reduced to R-3 for walls on 24” centers
Residential EnvelopeSteel-Frame Floors
Table 402.2.5
Conditioned Space
attic
Residential EnvelopeSpecific Requirements
Building Envelope consists of:FloorsSlabsCrawlspacesWalls
• Above grade• Below grade• Mass walls
FenestrationCeilings
Applies to slabs with a floor surface < 12 inches below grade
R-10 (typically 2 inches) insulation in Zones 4 and above
Must extend downward from top of slab a minimum of 24” (Zones 4 and 5) or 48” (Zones 6, 7, and 8)
Insulation can be vertical or extend horizontally under the slab or out from the building
Insulation extending outward must be under 10 inches of soil or pavement
• An additional R-5 is required for heated slabs
• Insulation depth of the footing or 2 feet, whichever is less in Zones 1-3 for heated slabs
Figure 2Flashing
ProtectionBoard
RigidInsulation
RigidInsulation
Slab
RigidInsulation
Slab
Figure 4
Slab
Figure 3
Residential EnvelopeSlab Edge Insulation
402.2.8
RigidInsulation
Slab
Bevel Cut
Residential EnvelopeSlab Edge Insulation
402.2.8
Conditioned Space
attic
Residential EnvelopeSpecific Requirements
Building Envelope consists of:FloorsSlabsCrawlspacesWalls
• Above grade• Below grade• Mass walls
FenestrationCeilings
Implies an unvented crawlspace (aka, conditioned crawlspace) Space must be mechanically vented or receive minimal supply
air (see Section R408 of the IRC) Exposed earth must be covered with a continuous Class I vapor
retarder
Residential Envelope Crawlspace Wall Insulation
402.2.9
Vented Crawlspace Requirements:
The raised floor over the crawlspace must be insulated.
A vapor retarder may be required as part of the floor assembly.
Ventilation openings must exist that are equal to at least 1 square foot for each 150 square feet of crawlspace area and be placed to provide cross-flow (IRC 408.1, may be less if ground vapor retarder is installed).
Ducts in crawlspace must be sealed and have R-6 insulation.
Unvented Crawlspace Requirements:
The crawlspace ground surface must be covered with an approved vapor retarder (e.g., plastic sheeting).
Crawlspace walls must be insulated to the R-value requirements specific for crawlspace walls (IECC Table 402.1.1).
Crawlspace wall insulation must extend from the top of the wall to the inside finished grade and then 24” vertically or horizontally.
Crawlspaces must be mechanically vented (1 cfm exhaust per 50 square feet) or conditioned (heated and cooled as part of the building envelope).
Ducts are inside conditioned space and therefore don’t need to be insulated.
Residential EnvelopeVented and Unvented Crawlspaces
IECC & IRC
Conditioned Space
attic
Residential EnvelopeSpecific Requirements
Building Envelope consists of:FloorsSlabsCrawlspacesWalls
• Above grade• Below grade• Mass walls
FenestrationCeilings
Exterior above-grade walls Attic kneewalls Skylight shaft walls Perimeter/rim joists Basement walls Garage walls (shared with conditioned space)
Residential Envelope Walls
Section 202, Tables 402.1.1, 402.1.3 & 402.2.5
Insulate walls including those next to unconditioned spaces
Don’t forget to insulate
rim joists
Residential EnvelopeAbove Grade Walls
Section 202, Tables 402.1.1, 402.1.3 & 402.2.5
Required R-value can be met with any combination of cavity or continuous insulation
Exception in zones 5-6: R-13 cavity plus R-5 sheathing meets R-20 requirement
h. “13+5” means R-13 cavity insulation plus R-5 insulated sheathing. If structural sheathing covers 25 percent or less of the exterior, insulating sheathing is not required where structural sheathing is used. If structural sheathing covers more than 25 percent of exterior, structural sheathing shall be supplemented with insulated sheathing of at least R-2.
Residential Envelope Wood Frame Walls
Table 402.1.1
R-19 + 6 in 2x6R-19 +12 in 2x8 or 2x10
R-19
R-19, 2x6R-19 + 6 in 2x8 or 2x10
R-13
Steel Joist Floor
R-13 +10 or R-19 +9 or R-25 +8R-21
R-13 + 9 or R-19 +8 or R-25 +7R-19
R-13 + 5 or R-15 +4, or R-21 +3 or R-0+10
R-13
Steel Framed Wall
R-49 2x4, or 2x6, or 2x8, or 2x10R-38
R-38 in 2x4, or 2x6, or 2x8R-49 any framing
R-30
Steel Joist Ceilings
R-38 + 5R-49
R-49 or R-38 + 3R-38
R-38 or R-30 + 3 or R-26 + 5R-30
Steel Truss Ceilings
Cold-Formed Steel Equivalent R-valueWood Frame R-valueTable 402.2.5
Steel-Frame Ceiling, Wall and Floor Insulation (R-Value)
Table keys on the wood-frame requirement for the corresponding building component
“R-X + Y” means R-X cavity plus R-Y continuous
Exception: In climate zones 1 and 2, the continuous R-value can be reduced to R-3 for walls on 24” centers
Residential EnvelopeSteel-Frame Walls
Table 402.2.5
What type Concrete block, concrete, insulated concrete form (ICF),
masonry cavity, brick (other than brick veneer), earth*, and solid timber/logs
Provisions Are assumed to be above grade walls
Residential EnvelopeMass Walls
402.2.4
* Earth includes adobe, compressed earth block, and rammed earth
Second (higher) number applies when more than half the R-value is on the interior of the mass (i.e., when the thermal mass is insulated from the conditioned space)
Residential EnvelopeMass Wall Requirements
Table 402.1.1
Basement Wall –>50% below grade
Below gradeBasement wall Exterior Wall –
<50% below grade
Residential EnvelopeDefining Below-Grade Walls
202, 402.2.7
≥ 50% below grade Otherwise treat as above-grade wall
Climate Zones R-Value1-2 03 5/13
4-5 10/136-8 15/19
Insulated from top of basement wall down to 10 ft below grade or basement floor, whichever is less
Residential EnvelopeBelow-Grade Walls
202, 402.2.7
• “X/Y” means R-X continuous or R-Y cavity
• 15/19 requirement can be met with R-13 cavity (interior) plus R-5 continuous (exterior)
• In zone 3, no insulation required in warm-humid counties
Residential EnvelopeBelow-Grade Walls
Table 402.1.1
Conditioned Space
attic
Residential EnvelopeSpecific Requirements
Building Envelope consists of:FloorsSlabsCrawlspacesWalls
• Above grade• Below grade• Mass walls
FenestrationCeilings
Residential Envelope Fenestration
303.1.3, Tables 303.1.3(1), 303.1.3(2), 303.1.3(3)
Doors and windowsNFRC rating or default table
• If not labeled with U-factor and SHGC, use default table (Tables 303.1.3(1), 303.1.3(2) & 303.1. 3(3))
No glass area limitsExemptions (prescriptive path only)
• Up to 15 ft2 of glazing per dwelling unit (Section 402.3.3)
• One side-hinged opaque door assembly up to 24 ft2 (Section 402.3.4)
Meet U-factorMeet SHGC
Residential Envelope Skylights
402.3.5
0.30 SHGC
Residential Envelope Locations with Window SHGC Requirements
Equal to climate zones 1A, 2A, 2B, 3A & 3B
Table 402.1.1
Can be used to satisfy U-factor and SHGC requirements
Subject to hard limits, even in trade-offs
Residential Envelope Fenestration: Area Weighted Average
404.3.1, 402.3.2
Hard limits on U-factor in northern U.S. (cannot be exceeded, even in trade-offs)
U-0.75 for skylights in Zones 4-8
U-factors of individual windows or skylights can be higher if maximum area-weighted average is below these limits.
Climate Zones U-Factor Maximum4-5 0.486-8 0.40
Residential Envelope Fenestration Trade-off Limits
402.5
Hard limit on Solar Heat Gain Coefficient in southern U.S. (Zones 1-3)
SHGC cannot exceed0.50, even in performance trade-offs
Residential Envelope Fenestration Trade-off Limits, cont’d
402.5
Less stringent insulation R-value and glazing U-factor requirementsSunroom definition:
One story structure Glazing area >40% glazing of
gross exterior wall and roof area Separate heating or cooling
system or zone Must be thermally isolated
(closeable doors or windows tothe rest of the house)
Can always meet Table 402.1.1 requirements with unlimited glass
Residential Envelope Sunrooms
202, 402.2,11, 402.3.5
Ceiling Insulation– Zones 1-4 R-19
– Zones 5-8 R-24
Wall Insulation– All zones R-13
Fenestration U-Factor– Zones 4-8 0.50
Skylight U-Factor– Zones 4-8 0.75
Residential Envelope Sunrooms
402.2.11, 402.3.5
Conditioned Space
attic
Residential EnvelopeSpecific Requirements
Building Envelope consists of:FloorsSlabsCrawlspacesWalls
• Above grade• Below grade• Mass walls
FenestrationCeilings
Residential Envelope Ceilings
402.2.1, 402.2.2, Tables 402.1.1 & 402.1.3
Requirements based on
Assembly type Continuous
insulation Insulation between
framing (cavity insulation)
Meet or exceed R-values
R-values are to be printed on the batt insulation or rigid foam board.
Blown-in insulation must have an insulation certificate at or near the opening of the attic.
The certificate should include: R-value of installed thickness Initial installed thickness Installed density Settled thickness/settled R-value Coverage area Number of bags installed
Insulation markers must be installed every 300 square feet and be marked with the minimum installed thickness and affixed to the trusses or joists.
Residential Envelope Ceilings
303.1.1, 303.1.1.1, 303.1.2
Ceiling insulation requirementsin R-value table assumestandard truss systems
Possibility ofice dam formations
Cold corners contributeto condensation andmold growth insome locations
Insulation
Insu
lati
on
Residential EnvelopeCeilings with Attics
402.2.1, Table 402.1.1
Prescriptive R-value path encouragesraised heel truss (aka, energy truss) If insulation is full height over exterior wall
top plate• R-30 complies where R-38 is required• R-38 complies where R-49 is required
Note: this reduction ONLY applies to the R-value prescriptive path, not the U-factor or Total UA alternatives
Insulation at fullthickness overexteriorwalls Insulatio
nIn
sula
tion
Residential Envelope Ceilings with Attics, cont’d
402.2.1, Table 402.1.1
Where insulation levels are required > R-30, and
The design of the roof/ceiling does not allow sufficient amount of space to meet higher levels,
R-30 allowed for 500 ft2
or 20% total insulated ceiling area, whichever is less
Note: This reduction ONLY applies to the R-value prescriptive path, not the U-factor or Total UA alternatives
Residential Envelope Ceilings without Attic Spaces (e.g., vaulted)
402.2.2, Table 402.1.1
R-19 + 6 in 2x6R-19 +12 in 2x8 or 2x10
R-19
R-19, 2x6R-19 + 6 in 2x8 or 2x10
R-13
Steel Joist Floor
R-13 +10 or R-19 +9 or R-25 +8R-21
R-13 + 9 or R-19 +8 or R-25 +7R-19
R-13 + 5 or R-15 +4, or R-21 +3 or R-0+10
R-13
Steel Framed Wall
R-49 2x4, or 2x6, or 2x8, or 2x10R-38
R-38 in 2x4, or 2x6, or 2x8R-49 any framing
R-30
Steel Joist Ceilings
R-38 + 5R-49
R-49 or R-38 + 3R-38
R-38 or R-30 + 3 or R-26 + 5R-30
Steel Truss Ceilings
Cold-Formed Steel Equivalent R-valueWood Frame R-valueTable 402.2.5
Steel-Frame Ceiling, Wall and Floor Insulation(R-Value) Table keys on the wood-
frame requirement for the corresponding building component
“R-X + Y” means R-X cavity plus R-Y continuous
Exception: In climate zones 1 and 2, the continuous R-value can be reduced to R-3 for walls on 24” centers
Residential EnvelopeSteel-Frame Ceiling
Table 402.2.5
Weatherstrip and insulate doors from conditioned spaces to unconditioned spaces (e.g., attics and crawl spaces)
Insulate to level equivalent to surrounding surfaces• e.g., required ceiling insulation = R-38, then attic hatch must be insulated to R-38
Provide access to all equipment that prevents damaging or compressing the insulation
Install a wood framed or equivalent baffle or retainer when loose fill insulation is installed
Residential Envelope Access Hatches & Doors)
402.2.3
Conditioned attic will not be found in the IECC
Refer to the IRC for requirements Insulate at roof deckRefer to IRC for ventilation (IRC Section R806.4)
Insulation for condensation control (IRC Table R806.4)
Residential Envelope Conditioned Attics
Lighting
A minimum of 50 percent of the lamps in permanently installed lighting fixtures shall be high-efficacy lamps
Residential LightingLighting Equipment: Prescriptive
404.1
Air Leakage
Floor
Window
Attic Hatch
Foundation
Chimney
Plumbing
Wiring
ExteriorDoor
Lights
Ceiling
Penetrations
Building thermal envelope
Recessed lighting
Fenestration Fireplaces
Residential EnvelopeMandatory Requirements: Air Leakage
402.4
Building thermal envelopeDurably sealed
Caulked Gasketed Weatherstrippe
d Air barrier
material Suitable film or
solid material
Residential EnvelopeAir Leakage Control
402.4.1
Windows and doors
Between sole plates
Floors and exterior wall panels
Plumbing Electrical Service access
doors or hatches Recessed light
fixtures Rim joist junction
Residential EnvelopeAreas for Air Leakage: Infiltration
402.4
Two options to demonstrate compliance
Whole-house pressure test• Air leakage <7 ACH when tested
at pressure of 50 Pascals• Testing may occur any time after
rough in and installation of building envelope penetrations
Field verification of items listed in Table 402.4.2.
Residential EnvelopeAir Sealing & Insulation
402.4.2.1, 402.4.2.2, Table 402.4.2
Residential EnvelopeAir Sealing & Insulation
Table 402.4.2
Exceptions Site-built windows, skylights, and doors
TYPE AIR INFILTRATION RATE
Windows, sliding glass doors, and skylights
≤ 0.3 cfm/ft2
Swinging doors
≤ 0.5 cfm/ft2
Residential Envelope Mandatory: Fenestration Air Leakage
402.4.4
New wood-burning fireplaces shall have gasketed doors and outdoor combustion air
Residential Envelope Fireplaces
402.4.3
Type IC rated and labeled as meeting ASTM E 283 when tested at 1.57 psf (75 Pa) pressure differential with no more than 2.0 cfm of air movement
Sealed with a gasket or caulk between the housing and interior wall or ceiling covering
Residential LightingRecessed Fixtures
402.4.5
Systems & Equipment
Equipment efficiency set by Federal law, not the I-Codes
Residential Mechanical Systems & Equipment
If primary heating system is a forced-air furnace At least one programmable thermostat/dwelling unit Capability to set back or
temporarily operate the systemto maintain zone temperatures
–down to 55ºF (13ºC) or –up to 85ºF (29ºC)
Initially programmed with:–heating temperature set point no
higher than 70ºF (21ºC) and –cooling temperature set point no
lower than 78ºF (26ºC)
Residential Systems Mandatory: Programmable Thermostat Controls
403.1.1
Prevent supplementary electric-resistance heat when heat pump can meet the heating load
Exception During defrost
Residential SystemsHeat Pump Supplementary Heat: Controls
403.1.2
Insulation (Prescriptive)– Supply ducts in attics: R-8
– All other ducts: R-6
Sealing (Mandatory)– Joints and seams shall
comply with IRC, Section M1601.4.1
– All ducts, air handlers, filter boxes and building cavities used as ducts shall be sealed (Section 403.2.2)
Building framing cavities shall not be used as supply ducts
Residential Systems Ducts
403.2
Location Requirement
Vented Attic R-8
Conditioned Space -
Vented Crawlspace R-6
Conditioned Crawlspace -
Basement – Conditioned
-
Basement – Unconditioned
R-6
Exterior Walls R-6
Residential SystemsDuct Location & Insulation: Examples
403.2
Duct tightness shall be verified by either of the following:
Post construction test• Leakage to outdoors: ≤8 cfm/per 100 ft2 of conditioned floor
area or• Total leakage: ≤12 cfm/per 100 ft2 of conditioned floor area
– tested at a pressure differential of 0.1 in w.g. (25Pa) across entire system, including manufacturer’s air handler enclosure
• All register boots taped or otherwise sealed Rough-in test
• Total leakage ≤6 cfm/per 100 ft2 of conditioned floor area– tested at a pressure differential of 0.1 in w.g. (25Pa) across
roughed-in system, including manufacturer’s air handler enclosure– all register boots taped or otherwise sealed– if air handler not installed at time of test
» Total air leakage ≤4 cfm/per 100 ft2
Exceptions: Duct tightness test is not required if the air handler and all ducts are located within conditioned space
Residential SystemsDuct Tightness Tests
403.2.2
R-3 required on – HVAC systems
• Exception: Piping that conveys fluids between 55 and 105°F
R-2 required on– All circulating domestic
hot water systems• Systems also require a
readily accessible manual switch
Residential SystemsPiping Insulation
403.3
Ventilation– Outdoor air intakes and exhausts shall have automatic
or gravity dampers that close when the ventilation system is not operating
Equipment Sizing– IECC references Section M1401.3 of the IRC
– Load calculations determine the proper capacity (size) of equipment
• Goal is big enough to ensure comfort but no bigger
– Calculations shall be performed in accordance with ACCA Manual J & S or other approved methods
Residential Systems Ventilation & Equipment Sizing
403.5, 403.6
Snow- and ice-melting system controls Automatic shutoff when pavement temperature is
> 50F and no precipitation is falling
Automatic or manual shutoff when outdoor temperature is > 40F
Residential Systems Snow Melt System Controls
403.8
Pool heaters– with a readily accessible on-off switch– fired by natural gas not allowed to
have continuously burning pilot lights
Time switches to automaticallyturn off and on heaters andpumps according to a presetschedule installed on swimmingpool heaters and pumps– Exceptions
• Public health standards requiring 24-hour pump operation
• Pumps operating pools with solar-waste-heat recovery heating systems
Residential Systems Pools
403.9
On heated pools If heated to >90°F,
vapor-retardant pool cover at least R-12
Exception: If >60% of energy
from site-recovered or solar energy source
Residential SystemsPool Covers
403.9.3
Systems serving multiple dwelling units shall comply with Sections 503 and 504 in lieu of Section 403
Residential SystemsMultiple Dwelling Units
403.7
U-Factor & Total UA Alternatives
U-factor AlternativeSimilar to Prescriptive R-Value but uses U-
factors instead• Allows for innovative or less common construction
techniques such as structural insulated panels or advanced framing
• Allows no trade-offs between building components
Total UA AlternativeSame as U-factor alternative but allows
trade-offs across all envelope components• Primary approach used in REScheck software
UA – U factor x area of assembly
Residential EnvelopeU-Factor and Total UA Alternatives
402.1.3, 402.1.4
Residential Envelope Climate Zone Requirements: U-Factor Table
Table 402.1.3
Climate Zones U-Factor Minimum
1 0.17
2 0.14
3 0.12
4 except Marine 0.10
4 Marine 0.57 same as above grade frame wall
5-8 0.57 same as above grade frame wall
Residential EnvelopeMass Walls: U-Factor
Table 402.1.3 Footnote b
Provisions When more than half the insulation is on the interior, the
mass wall U-factors:
Simulated Performance
Requires computer software with specified capabilities (local official may approve other tools)
Includes both envelope and some systems– Are treated equally in standard and proposed design
Allows greatest flexibility– Can trade-off tight duct systems
Defines compliance based on equivalency of calculated energy or energy cost
Section 405 specifies “ground rules”– These will generally be “hidden” in compliance software
calculation algorithms– Very similar ground rules are used in home federal tax credits
and ENERGY STAR Home guidelines
Residential Envelope Simulated Performance Alternative
Section 405
Software Tools for ComplianceREScheck™
www.energycodes.gov
REScheck™ DOE’s residential compliance software
(Windows or Mac version)
Desktop Software ToolsDesktop Software Tools Web-Based ToolsWeb-Based Tools
No-cost, easy-to-use software that will demonstrate compliance.
www.energycodes.gov/software.stm
Overview of Tool
–Various Screen and Options
–Compliance Methods
–AreaCalc Spreadsheet
–Reports
REScheck™
MAIN STEPS
1. Select the Appropriate Code
2. Complete Project Screen: location, building characteristics, and project
details (optional)
3. Enter Building Components
In many cases, components with the same construction characteristics can
be totaled and entered as one component.
Example: If all exterior walls are wood frame 16"o.c. with R-13 cavity
insulation, sum the gross area of every exterior wall and enter one wall
component
4. Enter Mechanical Equipment (Optional)
5. View/Print the Compliance Report
6. Save the Data File and the Report
REScheck™
PREFERENCES
• Edit Menu
General
File Options
Beyond Code
Version Update
REScheck™
PREFERENCES
• Edit Menu
• Project Details
• Set default settings for ENVELOPE and CODE
• Orientation is primarily required for the performance compliance method.
REScheck™
PREFERENCES
• Edit Menu
Applicant
Input information about the
Owner and Designer
REScheck™
PREFERENCES
• Edit Menu
Reports
Signature Lines
Email report
REScheck™
REScheck™
REScheck provides the option of 2 Compliance Paths-• UA Tradeoff -- The traditional
REScheck trade-off approach is based on trading thermal conductance (U-factor times surface area) between envelope components.
• Equipment Performance -- Involves an hour-by-hour energy simulation to determine whether the HVAC efficiency improvements make up for an otherwise failing envelope.
• REScheck requires a few additional inputs (e.g., orientation) to support the energy simulation.
• To comply with the 2009 IECC, you must pass by EITHER the UA Tradeoff index OR the Equipment Performance index, but you do not need to pass both.
Compliance Methods- UA Trade Off- Performance Alternative
UA Trade Off-• U Value – Table 402.1• SHGC – Table 402.1
Performance Alternative• Specify – Wall orientations• Existing Buildings cannot be Analyzed
using REScheck• Only New Construction• Mechanical Systems• SHGC Permitted – 0.50 (Climate Zones 1-3)
REScheck™
REScheck™
Envelope Screen• Changes based on code and/or location selected
– SHGC column– Orientation
For the Performance Alternative• Need to Specify Orientation of All walls and
Windows• Need to specify efficiency of heating and
cooling systems
REScheck™
Mechanical tab in
REScheck is optional. • Mechanical systems entered in
REScheck should be the primary
HVAC system.
• Emergency back up heat-
should not be entered in
REScheck.
• If equipment efficiency exceeds
minimum requirements- high-
efficiency equipment credit is
applied as a percent increase in
the code house UA.
REScheck™ Screen Operations
Screen Operations
Compliance Bar
Status Bar
Color : Red• Indicative of Non-
Compliance• Indicative of Incomplete
informationColor: Green• Indicative of
ComplianceColor: Blue• TBD
REScheck™ Area Calc Spreadsheet
• A spreadsheet-like interface is used to calculate window, door, skylight, roof, wall, and floor areas.
• These areas can then be
transferred directly into REScheck where the code compliance results for those assemblies can be displayed.
REScheck™ View/Print Reports
View/Print Reports
• Compliance Certificate
• Inspection Checklist
• Panel Certificate
REScheck™
DEMONSTRATION
REScheck™ Compliance Certificate
REScheck™ Compliance Certificate
REScheck™ Compliance Certificate
REScheck™ Compliance Certificate
REScheck™ Inspection Checklist
Inspection Checklist
• Mandatory requirements• Code presumes these
requirements are met• Moisture control• Building mechanical
systems and equipment• Service water heating• Duct construction and
insulation
The Shifting Arizona Market
Single-Family Building Permits:Phoenix and Maricopa County
Case Study Residential Remodel
& photo tour
Residential Case StudyRetrofit of Existing Building: Central Phoenix
Before Retrofit Building Features• 2 x 4 wood framed construction, R-13 batt
insulation
• Wood framed roof construction, no attic
insulation
• Single pane windows, vinyl and wood frame
• Gas furnace, low-efficiency air conditioner
• INEFFICIENT HOUSE
• LEAKY AND UNINSULATED
• HIGH ENERGY BILLS
• PRE-RETROFIT HERS INDEX: 238
Residential Case StudyRetrofit of Existing Building: Central Phoenix
YouthBuild
STRATEGY
- Reduce Building Envelope Heat Gain and Loss
- Reduce Internal Heat Gains- Reduce Air Infiltration and Leakage
Consequently, Heating & Cooling Loads were significantly LOWERED- Install high efficiency heating and cooling system
Residential Case Study Retrofit of Existing Building: Central Phoenix
STRATEGY: REDUCE ENVELOPE LOADS
Residential Case Study Retrofit of Existing Building: Central Phoenix
BUILDING ENVELOPE
• WindowsPreviously: single pane, with high U-value
Replaced by: double pane, low-e insulating glass
• Attic Previously:
negligible, misaligned roof insulation
Replaced by: R-38blown-in roof
insulation
Description IECC Case Study
Ceilings R-30 R-38
Windows U Value
0.65 0.33
INSULATION: BEYOND CODE
FENESTRATION: BEYOND CODE
STRATEGY: REDUCE INFILTRATION
INFILTRATION AND DUCT LEAKAGE
• Air Infiltration- a major cause of energy loss in homes
• Cracks and crevices allow for air leakage – leading to higher heating and cooling loads.
• Up to 40% of the home’s energy can be lost through the attic.
• The EnergyComplete system used in the case study project reduces whole house infiltrationExisting House 2465 CFM @
50pa22.08 ACH@50pa
Retrofitted House
1000 CFM @ 50pa
8.9 ACH @50pa
Code Compliant House
800 CFM @50pa
7 ACH @ 50pa
Residential Case Study Retrofit of Existing Building: Central Phoenix
INFILTRATION: Significantly BETTER
STRATEGY: REDUCE INTERNAL LOADS
INTERNAL LOADS
• High efficiency lighting• EnergyStar certified
appliances• Dishwasher• Refrigerator
Residential Case Study Retrofit of Existing Building: Central Phoenix
STRATEGY: REDUCE INTERNAL LOADS
HEATING AND COOLING SYSTEM• High efficiency heating and cooling
systems.
• Old Domestic Hot Water System Replaced by an Instant Hot water system, Natural Gas, 0.80 EF.
System Code Case Study
Gas Furnace 80AFUE 94AFUE
Air Conditioner SEER 13 SEER 16
Residential Case Study Retrofit of Existing Building: Central Phoenix
HEATING & COOLING: BEYOND CODE
After Retrofit Building Features
Residential Case Study Retrofit of Existing Building: Central Phoenix
• 2 x 4 wood framed construction, R-13 batt
insulation
• R-5 exterior continuous insulation
• R-38 roof insulation
• Double pane windows
• Gas furnace, high-efficiency 94 AFUE
• High-efficiency AC – 16 SEER
• Reduced Infiltration and duct leakage
• Insulated supply and return ducts
• EFFICIENT HOUSE
• POST-RETROFIT HERS INDEX: 58
Residential Case Study NAHB National Green Building Program
HERS Index is a scoring system
established by the Residential Energy
Services Network (RESNET)
238
Post-
retrofit
Pre-retrofit
58
42% more
efficient
180% more
efficient
Estimated
Monthly
Electricity
Charge
Residential Case Study NAHB National Green Building Program
Estimated
Annual
Utility SAVINGS
HERS
Ratings
Residential Case Study Retrofit of Existing Building: Central Phoenix
1204 E Oregon
purchase price – 55ksales price – 160k
days on market - 25
Residential Case Study Retrofit of Existing Building: Central Phoenix
Video – Case Study
Resources
Resources
• http://www.iccsafe.org• http://www.energycodes.gov• http://bcap-energy.org• http://www.naseo.org• http://www.eere.energy.gov• https://energycode.pnl.gov/REScheckWeb/• https://energycode.pnl.gov/COMcheckWeb/• http://resourcecenter.pnl.gov/cocoon/
morf/ResourceCenter
Welcome
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