energy conserving design details
DESCRIPTION
This two-hour lecture will cover residential design features and choices that may help to conserve energy. The discussion will include building siting and orientation issues, building envelope details, glazing, shading structures & devices, thermal mass and energy-conserving landscape elements. We will also briefly discuss how interior space lay-out can affect energy efficiency.TRANSCRIPT
The Green Roundtable
Energy Conserving
Design Details
and
The Green Roundtable(copyright © Green Roundtable 2007)
Green Roundtable
Consulting, education, training and strategic planning
to create healthy environments by integrating principles of
sustainability into mainstream planning, design and construction.
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Objectives
- Introduce you to basic concepts of energy
conserving design
- Help you develop the right mind-set & approach to
guide and inform future projects
- Provide some specific strategies/ elements to get
you started
- Demonstrate ways that these measures provide
benefits beyond energy conservation
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Food for thought….
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A sobering fact…
It has been estimated that in order for the
current population of the Earth to live at the
same quality of life as the industrialized
nations, it would require the resources of four
‗Earth equivalents‘.
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More sobering facts…
Half of U.S. greenhouse gas emissions come
from buildings (construction/ operation)
Buildings account for nearly half of the total
energy use in the United States
Buildings represent the single largest energy
consumer in the U.S., followed by the
transportation sector
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The Green Roundtable(copyright © Green Roundtable 2007)
Additional housing sector facts…
There are more than 76 million residential
buildings in the USA today
Estimates of residential energy consumption
as a proportion of the nation‘s total energy
load range from around 20 – 40%
The average size of a U.S. single-family
house has increased by 33% since 1975
From 2000 to 2005, winter heating costs for
natural gas increased by 115%, oil by 135%,
and electricity by 18%
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Additional housing sector facts…
According to HUD, if Americans can reduce
home energy use by 10% over the next ten
years (a doable number!), it will be the
energy equivalent of 40 new power plants
(600 Mw) and the greenhouse gas equivalent
of 25 million vehicles
The vast majority of the total life-cycle
energy consumed by a home is operating
energy (vs. the energy that goes into
building it)
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A key focal point in green design:
Since buildings are so energy-intensive
in their construction, operation and
maintenance, much of green design
focuses on ways to moderate this
energy consumption
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General approaches
- Work with nature; take advantage of site
- Pay attention to building envelope details
- Use natural/ passive ventilation & cooling strategies
- Use efficient lighting & equipment
- Choose design approaches that improve efficiency
- Improve efficiency through effective space layout
- Consider scale!
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Low-hanging Fruit
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Low cost, big return
• Insulate hot water pipes (pipes closest to water
heater first)
• Install faucet aerators & automatic faucets
• Install low-flow shower heads
• Install a programmable thermostat
• Carefully weatherstrip & air seal
• Use expanding foam insulation to plug obvious holes
in building envelope
• Use gasketed/ enclosed electrical receptacles
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Low cost, big return- continued
• Install dimmer switches & occupancy sensors
• Buy Energy Star anything! (if it affects energy use)
• Use CFLs!
• Use zone lighting
• Use motion sensor outdoor lights
• Put timer switches on bathroom fans
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Site/ Building Orientation
• Know the site! Visit during different times of year.
Set up on-site monitoring; Collect data from various
resources.
• Understand:
- Prevailing winds
- On-shore & off-shore breezes
- Sunshine patterns (insolation)
- Shading/ obstructions
- Topography
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Climate data/ maps
• http://www.nrel.gov/gis/maps.html- Solar, Wind
resources
•Topographical maps:
http://store.usgs.gov/scripts/wgate/ZWW20/!?~langua
ge=en&~theme=GP&OSTORE=USGSGP&~OKCOD
E=START
•Sunpath diagrams:
http://www.luxal.eu/resources/daylighting/sunpath.shtml
• OLIVER- MassGIS Online Data Viewer:
http://maps.massgis.state.ma.us/massgis_viewer/index.htm
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The Solar Pathfinder
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Using the site
• Take advantage of existing vegetation if possible-
deciduous trees for shading; coniferous trees as
wind breaks
• Site structure on south-facing slope for maximum
solar gain; take advantage of wind & solar resources
• Use natural terrain features to protect structure from
cold winter winds
• Site structure downwind from lakes, ponds, wetlands
for natural cooling
• Take advantage of hills that funnel breezes
• Use earth-berming if topography permits
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Building orientation/ layout
• Orient structure along East-West axis; i.e. long side
facing south
• Minimize glazing area on north, northeast & west-
facing walls
• Maximize glazing on south-facing walls to
maximize winter solar gains
• Incorporate buffer spaces in structure- closets along
outside walls, vestibules, enclosed porches, etc.
• Minimize surface area-to-volume ratio
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Green Practice:
Improving the Building Envelope
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Building envelope, definition
All of the elements of a building that separate and
isolate the outdoor environment from the indoor
environment. This may include walls and wall finishes,
roofs and roof finishes, doors, windows, skylights and
basement floors and walls.
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Key Principle- Saving home energy
As a general rule, for the average home/
homeowner, the greatest energy savings will be
achieved through managing the demand side of
the equation, rather than the supply side.
In other words, you’ll get better bang for your buck
through energy conservation measures, like insulating
& minimizing air infiltration, than incorporating
expensive renewable energy systems such as wind
and solar.
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An exception:
Exceptions to this may include passive solar, and
situations where you qualify for a substantial rebate
and/or credit for other renewable energy systems
(keep in mind the embodied energy of systems
though!)
There are other compelling reasons to perform
upgrades like this, such as reduced reliance on
foreign energy resources, promotion of renewable
energy & local industry, passive survivability, etc.
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Preventing heat loss
• Air seal (prevent infiltration)
• Best bang for buck through air sealing! Begin here!
• Insulate
• Use landscape features- vegetative shields, etc.
• Address lifestyle issues
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Building envelope, functions
• Protect structural elements and interior of structure
from weather, esp. moisture
• Help to maintain proper thermal regime within
structure
• Help to maintain proper humidity regime within
structure
• Prevent infiltration of outside air and contaminants
• Acoustically isolate interior of structure from outside
noise
• In essence, act as ‗membrane‘ for the structure
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Building envelope failure
• External water leaks leading to:
-Damaged structural elements
-Damaged interior finishes
-Insulation failure
-Damaged interior furnishings and appliances
-Mold problems
• Air leaks leading to:
-Infiltration of unconditioned air/ Drafts
-Direct escape of conditioned air to outside
-Infiltration of outdoor contaminants
• Excessive accumulation of interior moisture in wall
cavities causing structural/ insulation failure & mold
• Excessive heat transfer from inside to outside
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Building envelope components
• Exterior finish- wood siding, fiber-cement, brick, etc.
• Weather membrane/ air barrier/ drainage plane-
building paper, Tyvek, Typar, etc.
• Exterior sheathing- usually plywood or OSB
• Wall/ ceiling cavities (inc. structural members &
insulation)
• Vapor retarders/ barriers
• Interior wall finish
• Doors & windows
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High-performance wall section
A high-
performance
wall section
(proposed for
consideration)
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Envelope Layer Option 3 R-Value Permeance
1
Cedar (Eastern white) or fiber-cement
clapboards 0.87 (Cedar)
2
Pactiv GreenGuard Raindrop
Housewrap/ Rainscreen1 N/A
3 3/4" XPS Foam insulation 3.75 1.2
4
1/2" Homasote sheathing (Structural
bracing; high recycled content;
formaldehyde-free) 1.2 17
5
5 1/2" Stud cavity (2 x 6 walls; 24" o.c.)
w/ Fiberglass batts or polyurethane
spray foam 19/ 37*
6
Thermo-ply sheathing (Vapor retarder;
R-value from radiant barrier effect) 3.5 .53 -.63
7 5/8" GWB (Dbl. layer for thermal mass)
0.45 (0.90 w
dbl. layer)
8
1 1/2" thick wood furring strips (for
radiant barrier effect; also, can move
electricals within thermal envelope) N/A
9 Air space 1 120
Total R-Value 29.77/ 47.77*
*w/ poly foam
High-performance wall section, key
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Codes and standards
• Sixth edition of MA building code was officially
superseded by 7th edition as of January 1st, 2008
• New MA energy code based on 2006 International
Energy Conservation Code; more stringent
• Better to follow Energy Star Homes or HERS
guidelines for maximum energy efficiency and code
compliance (see resources slide)
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Minimizing air infiltration (sealing building envelope)
• Min .35 Air changes per hour (ACH) for good
ventilation; max .50 for energy efficiency (Energy
Star)
• Openings to attic spaces are some of worst offenders
• Seal obvious openings- pipe penetrations, attic
scuttles, electrical receptacles, recessed lights, etc.
• Any place where two building planes meet is good
candidate for air sealing
• For additions/ new construction, use exterior air
barrier to minimize infiltration
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Housewrap to
minimize air
infiltration &
protect from
moisture
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Blower door
test to
measure air
leakage
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Air leakage pathways
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Air leakage proportion through various pathways
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Attic hatches/ scuttles are a major leakage pathway
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A commercial solution for attic openings
See also www.efi.org
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Insulate header/ rim joists w/ rigid foam & expanding foam
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Seal joints between intersecting planes w/ expanding foam
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Fireplaces are usually NOT an effective heating appliance!
They lead to excessive heat loss via drafts up chimney.
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Air sealing, online product
sources
• efi.org
• conservationtechnology.com
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Insulating
• Resistance to heat flow (insulating ability) measured
in R-value; not important to know how this is derived;
mainly need to know that it‘s a relative scale of
effectiveness, and the higher the R value, the better
the insulating value
• Code represents absolute minimum; newer code
has more stringent requirements; tied to window area;
R-49 ceiling, R-21 walls, R-30 floors, R-13 basement
typical
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Insulating guidelines
• Remember that if you use A/C you are minimizing
cooling expense by buttoning up your house as well
as heating expense
• Go for low-hanging fruit- e.g. add more attic
insulation first if it is accessible and is not well
insulated; Don‘t forget the basement!
• Look for additional opportunities to insulate (other
than typical wall/ ceiling cavity insulation)
• Try to eliminate bridging (perimeter) heat loss
through structural elements, as it greatly reduces
overall insulation effectiveness
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Bridging heat loss
• Eliminate with:
-Double wall construction (very expensive!)
-Foam skin
-Cross-banding attic batt insulation
• Conductive heat loss through structural members
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Bridging heat loss- snow melts over roof rafters
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Bridging heat loss caused wall-staining over structural members
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Bridging
heat
loss through
sill plates
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Layer of foam
minimizes bridging
loss through sill;
top of concrete
foundation wall
will also receive
layer of foam
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Install continuous soffit vents
here
Provide continuous vent (ridge) here
Attic living space
Insulation baffle
(green)
Continuous airflow (blue) from soffit
to ridge; minimizes risk of ice dams,
minimizes moisture accumulation in
rafter cavities, keeps living space
cooler in summer and may extend life
of roof
2” XPS foam board
insulation
Rafter cavity insulation
(fiberglass typical.)
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Insulation Baffle
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Fiberglass batt insulation
• R 3.3 – 3.5 per inch
• No inherent air-sealing characteristics
• Relatively inexpensive
• Look for formaldehyde-free binders and recycled
content
• Need to avoid inhaling dust during installation
• Moderate to high embodied energy
• Can be rendered permanently useless if it gets wet
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Cellulose insulation
• R 3.5 per inch; 3.7 if wet blown
• Provides air-sealing characteristics if wet blown
(―damp spray‖; ―dense pack‖); professionally installed
• Relatively inexpensive
• Need to avoid inhaling dust during installation
• Low embodied energy
• Usually contains high recycled content (made from
newsprint)
• Moisture tolerant; can dry out and remain effective
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Extruded polystyrene (XPS)
• R 5.0 per inch
• Good air-sealing characteristics if edges foamed and
seams taped; closed-cell, moisture-resistant
• Relatively expensive
• Acts as vapor barrier at thicknesses > ¾ inch
• Can be difficult to install
• High embodied energy; many use HCFC blowing agents
• Must be protected from flame with min. ½ in drywall
or equivalent
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Polyisocyanurate rigid foam
• R 7.0 per inch
• Good air-sealing characteristics if edges foamed and
seams taped; somewhat moisture resistant (esp. foil-faced)
• Relatively expensive
• Can be difficult to install
• High embodied energy
• Acts as radiant barrier if foil faced (and facing ¾‖
min. air space)
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Icynene™ spray foam
• R 3.6 per inch
• Very good air-sealing characteristics; moisture-resistant
• Expensive
• Does not produce harmful smoke; does not burn
• Professionally installed
• Relatively high embodied energy
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Polyurethane spray foam
• R 6.7 per inch
• Excellent air-sealing characteristics
• Expensive
• Closed-cell; moisture resistant; may add structural
integrity
• Professionally installed
• Relatively high embodied energy
• Soy-based equivalents now available (see
biobased.net for one example)
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Icynene
application
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Additional Insulating Opportunities
• Be creative!
• Examples:
- Behind built-in bookcases
- Behind cabinets
- Closet walls & ceilings
• Capitalize on opportunities to insulate, such as
when you have exposed exterior wall cavities during
remodeling projects
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Thermograph to check heat loss through walls (insulation effectiveness)
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Ventilation & Vapor Barriers
• Moisture control as it relates to:
-Mold potential
-Structural failure
-Insulation failure
-Aesthetic issues
Issues:
• Indoor air quality (IAQ)
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Ventilation
• It‘s almost impossible to make an old house too
tight
• Even in a tight house a bathroom fan is generally
enough to provide adequate ventilation; control w/
timer (and/or humidistat)
• Provide dedicated combustion air sources for large
combustion appliances like furnaces & fireplaces
• Control internal sources of excessive moisture
• Proper attic ventilation may extend life of roof and
help to eliminate ice dams
• Extremely tight houses may need heat-recovery or
multi-port supply ventilation systems
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Vent bathroom vans to outside!
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Other ventilation strategies
• Heat recovery ventilators
• Multi-port exhaust ventilation
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Vapor barriers/ Retarders
• Prevent transfer (and accumulation) of internal
moisture into wall/ ceiling cavities
• Always on warm side of insulation (winter) for this
part of country (northeast U.S.)
• Asphalt-impregnated kraft paper is excellent vapor
retarder
• In this part of country, vapor retarders are generally
better than vapor barriers; vapor retarders allow wall
to dry from the inside as well as outside
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Vapor barriers, continued
• Eliminating air leaks in inside wall finishes minimizes
vapor transfer into wall cavities
• For retrofit of vapor barrier (w/ blown-in insulation for
instance), consider a vapor barrier paint
• New ‗smart‘ materials like Certainteed‘s Membrain
create variable vapor barrier
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Windows
• ‘Low-e’ coating reflects heat back into structure
• Performance measured in ―U-value‖; inverse of R-
value; measure of material‘s ability to conduct heat;
the lower the U-value, the better
• Double-glazed, argon filled preferred; Diminishing
returns with triple glazing
• Typical heat loss through windows about 20%
• Look for U-value of .35 or less
• Always look for Energy Star & NFRC labels
(energystar.gov; nfrc.org)
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NFRC Label
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Windows
• Provide nighttime insulation
• Used ‗tuned‖ glazing strategies
• Incorporate/ install overhangs & other shading
devices where appropriate
• E.g., Use windows w/ low SHGC on west-facing
windows; high SHGC on south-facing
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Dbl-wall, cellular
shades provide
insulating value
Window insulation
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Guide rails/ tracks minimize
air leakage at edges
Window insulation
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Energy Conserving
Design Strategies (a sampling)
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The jumping off point…
ScaleScaleScale
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Design Strategies: Thermal mass
Thermal mass:
• Can be used to store heat in winter
• Can help to moderate temperatures year-round
• Key element in passive solar design
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Thermal mass: How to incorporate
• Masonry veneers on exterior walls
• Masonry finishes on interior walls & floors
• Fireplaces, chimneys & interior masonry features
• Thickened walls- e.g.double drywall layer
• Green roofs
• Cob & masonry construction
• Water features/ elements
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Thermal mass: additional benefits
• Acoustic comfort
• Increased structural integrity in some situations
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Design Strategies: Green roofs
• Properly designed, can pay for themselves in 10 –
15 years via reduced energy cost
• Especially effective in reducing cooling costs
• By some estimates, can reduce cooling costs by up
to 30% in single-story structures
• See www.greenroofs.com (industry ass‘n) &
www.conservationtechnology.com (supplier example)
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Modular green roof system
See:
http://www.liveroof.net/ &
http://www.westonsolutions.com/pdf_docs/B-D066-
GreenGrid.pdf
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• Can provide stormwater management
• Reduce urban heat islands
• Help to minimize global warming by conserving energy
• May extend the life of your roof
• Provide green space & wildlife habitat
• Improve acoustic comfort
Green roofs: additional benefits
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Design Strategies: Passive solar
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Passive solar
Basic requirements:
• Collect it…
• Retain it…
• Store it…
• Distribute it…
Free heat from the sun; ‗greenhouse effect‘ (good
kind!); good southern exposure/ solar aperture needed
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5 Major elements of
Passive Solar
• Aperture/ Collector (glazing)
• Absorber
• Distribution
• Thermal storage (mass)
• Control
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Requirements
• Glazing area to collect sunlight- 7% rule- So.-facing
• Window insulating system (and good building
envelope insulation) to keep heat in at night
• Thermal mass- needed to store heat if net window
area is more than 7% of total floor area
• Shading—vegetation (deciduous), or shading
structures like awnings, roof overhangs and
pergolas, to prevent overheating during warmer mos.
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Requirements,cont.
• Distribution system—to remove excess heat to
other parts of house where it may be needed in
winter
• Ventilation system—to remove excess heat to
outside during warm weather
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Passive Solar Rules-of-Thumb
• Orientation of aperture area should be within 30
degrees of true south
• Aperture should ideally be shade-free from 9am –
3pm
• Direct gain systems are most common and easiest
to integrate into most designs; glazing should not
exceed 12% of building floor area
• South-facing glass should be vertical and should
have some kind of overhanging to shade from
summer sun
• Thermal mass can help to moderate temperature in
summer as well as store heat in winter
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Passive Solar Rules-of-Thumb
• Skylights should be avoided on all but north and
northeast-facing roof surfaces, as they can otherwise
contribute to overheating in the summer, and won‘t
provide appreciable gains in the winter due to low
angle of sun
• Deciduous trees can provide good summer
shading, but should not be located too close to
house/ sunspace, as trunk/ branches may provide
too much shade in winter
• In sunspaces, may need powered ventilation to
minimize summer overheating
• Well designed passive solar can provide 5 –25% of
space heating needs with no added cost
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Angled glass may not be the best configuration,
especially without an overhang!
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Skylights may contribute to summer overheating
and winter heat loss.
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Design strategies: Advanced Framing
• Saves on labor cost since fewer ―sticks‖ installed
• Saves on framing lumber expense
• Reduces lumber disposal cost/ impact
• Savings estimates range to 20% of overall framing
expense
• Improves thermal envelope of building– more
places to insulate!
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Advanced framing & efficiency
• Provides more room for insulation!
• Reduces bridging heat loss
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Advanced Framing
• ―Right-sized‖ headers; insulated, engineered headers
• Features 2 x 6 studs on 24‖ centers
• Jack studs eliminated at window openings
• No headers in non-load bearing partitions
• Single top plate if trusses/ roof rafters placed
directly over wall studs
• Open corner framing (2-stud corners)
• Ladders at T-intersections
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Frost-protected Shallow Foundations
• Improves thermal performance
• Reduce excavating expense
• Reduce site impact
• Reduce material expense
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Design Strategies: Natural daylighting
• Can reduce lighting loads and cooling loads
• Residential systems typically consist of skylights,
clerestory windows or tubular daylighting devices
(TDD‘s; ―sun tubes‖ or ―light tubes‖)
• Improves indoor environmental quality
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Design Strategies: Natural daylighting
• Skylights in south, southwest and west-facing roofs
can contribute to summer overheating
• Skylights in more north-facing roof surfaces can
contribute more light on cloudy days
• TDDs may contribute less to overheating
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Sky tube (TDD)
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Natural daylighting
• Light-colored walls reflect light deeper into structure
• Light shelves can serve the same purpose, and
accomplish this w/o excessive glare; they provide
shading as well
• Combine daylighting strategies with photo-resistor
controlled lights to avoid excessive lighting during
daytime
• Wide windowsills/ shelves can reflect light as well,
but may contribute to glare
• Landscape features can be utilized for reflecting
light into interior as well (paved surfaces, water
features, etc)
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Light shelves shade window
while providing natural daylight
via light reflected from top
surface
Can help light to penetrate
deeper into structure
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Suggested Room Surface Reflectances:Ceilings: > 80%Walls: 50%-70%Floors: 20%-40%Furnishings: 25%-45%
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RADIANCE is a lighting and
daylighting visualization tool
developed by LBNL and is available
over the web:
http://radsite.lbl.gov/radiance/
Lighting & Daylighting Analysis
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Alternative building technologies
• Structural Insulating Panels (SIPs)
• Modular construction
• Insulating concrete forms (ICFs)
• Hydronic radiant floor heating systems
• PEX (cross-linked polyethylene) domestic water
supply piping
• Google these!
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Green Practice:
HVAC/ Plumbing
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HVAC & Plumbing Systems
• ―Right-size‖ systems using analysis tools (Manual J)
rather than rule-of-thumb methods; a right-sized
system can be up to 40% smaller than a
conventionally-sized system
• Use structured plumbing & PEX piping
• Use demand pumps in DHW supply system
(gothotwater.com)
• Use heat recovery devices on DWV pipes
(gfxtechnology.com)
• Use instantaneous hot water heaters (tankless)
• Use zoned heating
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Tankless water heaters
• Examples of brands: Rinnai, Noritz, Takagi
• Gas-fired typically more responsive and can provide
needed capacity more effectively
• Cost more than standard water heaters but last longer
• More choices as to location/ placement
• Direct-venting; e.g. can exhaust through wall
• Save energy by eliminating standing heat loss (vs.
conventional tank-style water heater); estimated savings
24 – 34%
• Look for min. flow rates of 0.3 – 0.5 gal./min.
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High-efficiency heating
• Boilers tend to have higher AFUE than furnaces
• Make sure heating systems have Annual Fuel
Utilization Efficiency (AFUE) of at least 83% for oil-
fired and 90% for gas-fired, and Seasonal Energy
Efficiency Rating (SEER) of at least 13 for cooling
systems
• Choose Energy Star! Right-size systems! (did I
mention that before?!)
• Closed-cycle, condensing-type boilers and furnaces
are more efficient; they extract additional heat from
warm flue gases
• These systems often don‘t need conventional flue pipe,
they can side vent, but they require a dedicated
combustion air source (coaxial flue pipe)
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The Green Roundtable(copyright © Green Roundtable 2007)
Ductwork
• Move duct runs into conditioned spaces (thermal
envelope) if possible
• Seal ducts; use duct mastic for this if possible,
otherwise make sure duct tape is UL listed
• Insulate ducts in unconditioned spaces; for cooling
(A/C) ductwork, make sure insulation has external
vapor barrier to minimize condensation
• When insulating ducts in unconditioned basement,
you may make basement too cold; insulate
basement walls instead
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Lighting
• Use natural daylighting strategies
• Use zone lighting
• Use solar landscape lights
• Use motion sensor outdoor lights
• Put timer switches on bathroom fans
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Appliances
• Buy Energy Star!
• Specify horizontal axis washing machines
They save water and energy
• Specify dishwashers w/ booster heater
(and lower water heater to 120 deg)
• Don‘t specify oversized AC equipment!
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The Green Roundtable(copyright © Green Roundtable 2007)
Cooling
Use ceiling fans w/ cathedral or high ceilings to
eliminate temperature stratification (both heating and
cooling season)
Shade air conditioner and heat pump condensers w/
vegetation or artificial shading (be careful w/ deciduous
vegetation) if you have to locate on sunny side
Locate AC/ heat pump condensers on N or NE or
NW side out of direct sun!
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Install awnings, overhangs and other shading
structures, such as pergolas
Use retrofit heat-reflecting window films on west-
facing windows (look for NFRC label); for new
windows, choose units w/ low solar heat gain
coefficient (SHGC)
Make sure attic space is well vented
Use whole-house fans to exhaust warm air from
house in summer; run mainly at night to flush w/ cool
air; close windows during very hot days
Cooling
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Cooling
Install radiant barriers on underside of roof rafters; can
help to warm in winter and cool in summer; don‘t
interrupt ventilation pathways
Use deciduous vegetation on south, SW and west
sides of structure for summer shading; use vines on
trellises too
Use coniferous (evergreen) trees/ shrubs to redirect
breezes/ wind
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Take advantage of prevailing winds for natural cooling
Maximize cross-ventilation
Use building elements to funnel winds (e.g. casement
windows)
Use light-colored shingles or roof membrane on very low
pitched or flat roofs
Use high-performance double roof or ―cool‖ roof, esp. w/
cathedral ceilings
Cooling
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General analysis tools
A general list of tools offered by the U.S. Department
of Energy are available over the web at:http://www.eere.energy.gov/buildings/tools_directory/subjects.cfm/pagename=subjects/pagename_menu=whole_building_analysis/pagename_submenu=load_calculation
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Standards/ Ratings/ Resources
• LEED for Homes (LEED-H)- www.usgbc.org
• Energy Star Homes- www.energystar.gov
• International Energy Conservation Code (IEEC)-
http://www.iccsafe.org/
• HERS (http://www.energy.ca.gov/HERS)
• Building America-
http://www.eere.energy.gov/buildings/building_america/a
bout.html
• Environmental Building News/ Greenspec-
http://www.buildinggreen.com)
•http://www.austinenergy.com/Energy%20Efficiency/Progr
ams/Green%20Building/Sourcebook/index.htm
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• Upcoming workshops
• Reference library
• Samples library
• Cyber Lounge
• Online resources at nexusboston.com (in the
pipeline)
• Local green building community
Use NEXUS as your green resource!
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Local Resources
The Green Roundtable(copyright © Green Roundtable 2007)
The Green Roundtable, Inc. (GRT) is an independent non-profit
organization whose mission is to mainstream green building and
sustainable design and become obsolete. We work toward this goal
by promoting and supporting healthy and environmentally
integrated building projects through strategic outreach, education,
policy advocacy and technical assistance.
www.greenroundtable.org
617-374-3740
www.nexusboston.com38 Chauncy Street, Boston
Located in downtown Boston, NEXUS
welcomes all to come ask questions,
research topics, and attend tours and
events on green building and
sustainable design innovation.
THANK YOU