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Building Better, TighterMore Efficient Homes
For Less
The how-to guide for builders
Steve RommeMarch 4, 2016
1
Agenda
• Introduction and outcomes
• Costs & benefits of building better
• How to build better, tighter homes for less
• Summary
• Q&A
2
Introduction
• 30 year career, residential building for 10 years– Business roles in accounting, manufacturing, marketing, new product
development and business leadership
– Building roles as a home builder, passive solar designer/installer and new home optimization specialist
• Now a partner at eFree Advisors– We act as part of the builder’s staff helping them build better homes and
guaranteeing the home’s performance
• We focus on building costs, energy costs and comfort
• We optimize, specify, verify and guarantee new home performance
• We introduce innovation and evaluate new products
3
Session Outcomes
• Share our knowledge and experience about– The costs and benefits of building better, tighter homes
– How to build tighter homes for less
– How to keep tight homes safe
– How you can implement this in your business
• Get you to take action– Start implementing!!
• Either do it yourself, or get someone like us to help
– It can seem overwhelming, but it’s really not
4
Making a Home More Efficient
• Two key costs– Lights and Appliances and Heating and Cooling
• Within heating and cooling– Insulation and infiltration are the main drivers
– Infiltration also affects insulation performance
5
Insulation36%
Infiltration29%
Windows19%
HVAC Efficiency
10%
Ventilation6%
Heating and Cooling Costs
Heating and Cooling
36%
Water Heating15%
Lights and Appliances
37%
Service Charges12%
Energy Costs
Our Experience Savings
6
Construction Type
Shell SqFt CFM50
% Better Than Code
Year 1 Energy Savings
Year 1 Mortgage Increase
Year 1 Net
Savings
20-Year Net
Savings
Annual CO2
Savings
Averages 8,746 0.08 45% $1,755 $1,194 $561 $38,636 16,875
ICF 7,975 0.09 35% $1,178 $1,440 -$262 $10,151 10,403
AF: 2x6/Cell/ZIP 10,981 0.08 41% $2,172 $2,220 -$48 $27,419 16,887
TF: 2x6/BIB/Sh/1" 9,985 0.07 45% $1,440 $1,368 $72 $20,255 17,249
TF: 2x6/Batt/Sh/1" 8,735 0.10 37% $1,254 $1,080 $174 $19,865 21,710
TF: 2x6/Batt/Sh/1" 7,642 0.12 38% $1,326 $1,140 $186 $21,045 11,798
ICF 4,590 0.09 42% $1,141 $900 $241 $30,871 9,464
AF: 2x8/Batt/Sh 6,787 0.10 40% $1,011 $696 $315 $23,270 11,890
ICF 9,605 0.06 48% $2,318 $1,992 $326 $36,807 17,398
SIP 12,556 0.08 72% $4,081 $3,720 $361 $60,092 35,089
AF: 2x8/Batt/Sh 5,833 0.08 33% $844 $480 $364 $18,308 7,551
TF: 2x6/Batt/Sh/1" 7,638 0.08 31% $1,085 $720 $365 $21,477 9,682
AF: 2x8/Batt/Sh 11,047 0.06 38% $1,665 $1,248 $417 $30,095 14,825
AF: 2x8/Batt/Sh 7,350 0.07 36% $1,062 $624 $438 $26,586 12,394
TF: 2x6/Batt/Sh/1" 7,690 0.13 34% $1,155 $672 $483 $36,009 10,208
AF: 2x6/Cell/ZIP 5,764 0.08 38% $1,145 $624 $521 $25,381 10,212
AF: 2x6/Cell/ZIP 10,064 0.13 62% $2,378 $1,836 $542 $50,760 27,928
AF: 2x8/Batt/Sh 6,406 0.05 32% $922 $372 $550 $23,047 8,251
ICF 9,660 0.06 53% $2,791 $2,208 $583 $75,382 26,486
ICF 7,974 0.10 60% $2,788 $2,184 $604 $70,615 22,476
AF: 2x8/Batt/Sh 6,887 0.07 36% $1,069 $444 $625 $26,468 10,003
AF: 2x6/Cell/ZIP 13,980 0.10 40% $2,407 $1,776 $631 $44,070 22,138
AF: 2x6/Cell/ZIP 12,956 0.05 44% $1,676 $1,044 $632 $34,539 20,549
AF: 2x8/Batt/Sh 7,323 0.09 38% $1,158 $504 $654 $25,210 11,510
TF: 2x6/Batt/Sh/1" 8,141 0.05 37% $1,696 $1,032 $664 $35,440 13,084
AF: 2x8/Batt/Sh 9,636 0.06 38% $1,494 $828 $666 $32,841 13,751
AF: 2x6/Cell/ZIP 10,119 0.04 37% $1,573 $900 $673 $39,864 15,561
AF: 2x6/Batt/Sh 9,470 0.05 40% $1,305 $624 $681 $34,385 15,463
AF: 2x8/Batt/Sh 7,561 0.08 37% $1,184 $492 $692 $33,714 12,565
AF: 2x8/Batt/Sh 10,509 0.06 37% $1,621 $876 $745 $36,072 14,844
AF: 2x6/Cell/ZIP 9,258 0.03 86% $3,324 $2,448 $876 $93,420 44,990
AF: 2x6/Cell/ZIP 12,529 0.07 53% $2,892 $1,944 $948 $56,747 26,179
TF: 2x6/Batt/Sh/1" 5,778 0.11 80% $2,704 $1,632 $1,072 $83,176 15,292
TF: 2x6/Batt/Sh/1" 9,371 0.08 49% $1,905 $828 $1,077 $46,431 19,370
TF: 2x6/Batt/Sh/1" 6,621 0.13 48% $2,054 $816 $1,238 $51,597 17,941
AF: 2x8/Batt/Sh 11,839 0.11 42% $2,370 $624 $1,746 $65,886 21,076
Our ExperienceInfiltration
7
3,000
5,000
7,000
9,000
11,000
13,000
15,000
- 0.03 0.05 0.08 0.10 0.13 0.15 0.18 0.20
She
ll Sq
Ft
CFM50/SqFt Shell
TF: 2x6/Batt/Sh/1"
TF: 2x6/BIB/Sh/1"
AF: 2x6/Cell/ZIP
AF: 2x8/Batt/Sh
ICF
SIP
FoE New Homes
Passive House
Infiltration and Insulation
• Infiltration = holes within the outer shell– Air escapes and takes heat and moisture with it
– Requiring more heat and humidification
• Insulation = material that slows heat transfer– Fiberglass and cellulose require controlled air movement to perform
– Foam controls the air within the material
– Fiberglass or cellulose are far less expensive, but are susceptible to infiltration
8
$0.0000 $0.0400 $0.0800 $0.1200 $0.1600 $0.2000
1" Spray Foam R6.4
1" XPS Foam R5
Spray Cellulose R21
BIBs R23
HD Batt R21
Batt R19
Cost / sq. ft. / R value Installed(includes framing factor)
Source: eFree Advisors Wall Analysis 2015
How to Build Tight and Safe
• Exterior Air Sealing
• Insulation
• Interior Vapor Sealing
• HVAC
9
Air and Vapor Sealing
• Two different sealing purposes
– Exterior air sealing keeps cold air out of the cavity• Smaller impacts on heating bills and structural durability
• Incomplete air sealing causes:– Outside winds can drive colder air through homes if vapor seal is defective
– Cold air can enter a cavity and circulate within, defeating the insulation
– Outside air can enter between studs and enter the cavity
– Interior vapor sealing keeps the home comfortable• Big impacts on heating bills, comfort, dryness and durability
• Incomplete vapor sealing causes:– Higher heating bills
– Cold drafts
– Dryness and the need for humidification
– Possible moisture, rot and mold issues
10
Air Sealing the Exterior
• Exterior surfaces that need to be sealed
– Exterior walls
– Exterior ceilings
– Exterior floors
11
Air Sealing the Exterior
– Exterior walls• Common method
– House wrap
» Alternatives are ZIP®, spray on material, and foam
• Key to successful installation– Completely cover the house from foundation foam to above the plane of the top plate
– Tightly install, overlap and tape joints
– Properly flash, lap and seal openings
– Seal penetrations
• Common issues– Garage walls and interior attic walls commonly missed
– Poor house wrap installation
– Unsealed penetrations
– Mud plate and bottom plate area
12
Air Sealing the Exterior
– Exterior ceilings/attics• Common method
– Vented attics need air sealed truss cavity ends
• Keys to successful installation– Vented attic spaces must have end caps that are sealed to the top plate and trusses
• Common issues include– Vented attics
» Truss cavity ends have blocking that is not air sealed to the top plate
– Unvented attics spaces
» Ends not well sealed allowing air to get under insulation
» Entire cavity vapor sealed (will work if perfectly sealed)
13
Air Sealing the Exterior
– Exterior or “exposed” framed floors • Common method
– Spray foam or house wrap
– Explained under insulation section
14
Air Sealing the Exterior
– Summary of Exterior Air Sealing:• Visual inspection is our only test method
– Post construction IR images can find bad areas, but it is usually too late to fix them easily
• Typical risks are:
– Less effective insulating properties that increase heating costs
– Interior wall condensation/wet spots
– Non-visual (within the cavity) moisture issues
15
Insulating
• Insulation Areas– Concrete floors and foundation walls
– Mud plate/box sill/rim joist area
– Exposed floors
– Above grade walls
– Ceilings
– Bonus rooms
16
Insulating
– Concrete floors and foundation walls• Common method
– Rigid foam under slab
» Below grade slabs typically include 1” foam as minimum, 2” maximum
» Foundation walls typically 2” foam exterior, rarely more or less
» Finished foundations typically 1” inside with R11 or R13 batt insulation
• Keys to successful installation– Knowing concrete is conductive
– Adequate edge insulation on above grade slabs
– Eliminating insulation voids as heat can be conducted through them
• Common issues– No insulation over footings
– No thermal break in thresholds
– Voids in insulation that cause heat leakage
– No interior rigid foam used when finishing walls
» Can be done, but cavity must be pretty tightly air sealed
17
Insulating
– Mud plate/box sill/rim joist area• Common method
– Closed cell spray foam
» Can use rigid foam and seal the edges
• Keys to successful installation– Access to all exterior rim sections
» Sometimes exterior rim joists pockets are closed and holes need to be drilled
– Completing air/vapor sealing and insulating at the same time by welding the foundation to the subfloor with 3”-4” of closed cell foam
» Some inspectors may limit spray foam to the area above the bottom of joist. In these cases, the sill plate connection to the foundation should be caulked
• Common issues– Use of improper foam or worse, just batts
– Application on wet or dirty material or in too cold of temps
– Incomplete coverage and air leaks
18
Insulating
– Exposed floors• Common method
– Closed cell spray foam
» Smaller areas spray 4” of foam on all exterior surfaces, or fill cavity
– Larger areas are properly air and vapor sealed and cavities filled with insulation
• Keys to successful installation– All exterior surfaces must be foamed with closed cell
» Specific designs can be developed to air seal the outside surfaces, vapor seal the inside surfaces and completely fill the cavity with insulation
• Common issues– No exterior air sealing causing reduced insulating effectiveness
– Poor interior air/vapor sealing causing drafts, cold spots and moisture issues
19
Insulating
– Above grade walls• Common method
– 24” OC with cavity insulation
» Cavity insulation typically used includes batt, BIB, blown cellulose
» Spray foam is not typically cost effective
– Rigid foam or ZIP® can be added to the outside, but usually not cost effective
• Keys to successful installation– Larger cavities need to be completely filled with no voids or risk of settling
– Smaller cavities (around windows/doors and between studs) need to be filled with foam or caulk depending on width
– Headers should be engineered to provide maximum depth for insulation, or framers should fill with sheet foam
20
Insulating
– Above grade walls• Overall common issues
– Lack of access behind showers, fireplaces, etc.
– Attic wall thickness of 2x4
– Lack of installer knowledge of the principles of insulating
• Common issues by insulation type– Batts tight within the cavity yet not over-compressed, split around wires and
cut around electrical boxes
– BIB filled around and behind electrical boxes and around wires and compressed or properly baffled to avoid settling over time
– Spray cellulose mixed properly to adhere and blown properly to compress material down while installing
21
Insulating
– Ceilings• Common method
– Blown fiberglass or cellulose
– Fiberglass batts in limited access areas
• Keys to successful installation– Wind block at ends over top plate
– Energy heels that provide full coverage to the outside edge of the top plate
– Specified thickness levels throughout ceiling area (sticks, label, chalk line)
– Treating walls separately <12”
– Baffles on higher slope sections to avoid sliding over time
– In limited access areas and sealed roof sections, completely fill cavity, or ensure no air gap exists on the bottom (drywall)
• Common issues– Lack of coverage over top plates
– Poor or uneven coverage especially in hard to reach areas
– Mounding insulation to cover wall sections
– Attic hatch is poorly insulated
22
Insulating
– Bonus Rooms -Big challenge and not cheap space» Common method
• Cavity insulation with good exterior air and interior vapor sealing required
» Keys to successful installation• Block and air seal joist ends
• Completely fill joist space ensuring there is no air gap on the top (under-side of the floor)
• Ensure the knee walls are insulated to R19 or greater and air sealed on the outside and vapor sealed on the inside
• Ensure ceiling is vapor sealed from the inside, has proper attic venting and has adequate insulation (R50 target)
» Common issues• Poor exterior air sealing
• Poor interior vapor sealing
• Cavity voids
23
Air/Vapor Sealing the Interior
• Interior surfaces requiring vapor sealing– Concrete floors and foundation walls
– Plates, box sills, rim joist area• Explained earlier
– Exterior walls and ceilings
– Penetrations
24
Air/Vapor Sealing the Interior
– Basement floor and foundation walls• Common method
– Plastic sheeting (poly) under slab – moisture
– Caulked slab to wall joint– earthen gases
• Keys to successful installation– Continuous poly wall-to-wall, overlapped, taped and run up walls
» Run on top of foam or under
» Penetrations taped around and sealed
– Use caulk to fill slab to wall joint (foam is a mess)
• Common issues– Poly is rarely taped on seams
– Poly has gaps between seams and floor penetrations are not sealed
– Slab to wall joint is not cleaned prior to caulking or not caulked
25
Air/Vapor Sealing the Interior
– Exterior walls and ceilings• Common method
– “Create an air-tight bag within the house”
– Continuous poly on all walls and ceilings
– Top plates foam-welded from attic
• Keys to successful installation– Good framing with built-in showers and fireplaces already insulated and polyed
– Framing, openings and exterior already sealed
– Insulation installers awareness of goals
– Pre-insulation and post insulation walkthrough
– Attic access sealed with weather stripping
26
Air/Vapor Sealing the Interior
– Exterior walls and ceilings• Common issues
– Poly installation
» Not overlapped, not taped, cut short or ripped
– Top plates not welded
– Interior walls intersections not sealed
– Window bump-puts
– Lower level wall connections to foundation
– Soffits/tray ceilings
– Attic hatches
– Fireplaces (they should be inside)
27
Air/Vapor Sealing the Interior
– Penetrations• Common method
– Caulk or foam
» Every opening including windows, doors, electrical boxes, plumbing, etc.
• Keys to successful installation– Pre-sheetrock all penetrations are sealed
– Post-sheetrock, all penetrations are rechecked and sealed to drywall
– Final inspection and touch-ups
28
Air/Vapor Sealing the Interior
– Penetrations• Common issues
– Windows and doors
– Recessed lights
– Electrical outlets
– Mechanicals
29
Air/Vapor Sealing the Interior
• Interior Air Sealing Summary– Most important thing YOU should be doing
• Best energy savings ROI
• Improves comfort
– No cold drafts
– Usually eliminates need for humidification
• Reduces building durability risks
– Doesn’t require special material
– Costs next to nothing to do
30
HVAC
• HVAC Overview– Critical to providing indoor air quality
• Closed combustion appliances eliminate risk
• Controlled ventilation provides efficient fresh air
– Indoor air quality will be measured in real time by homeowners very soon –are you ready?• Current systems can provide CO2, CO, VOC levels and particulate levels
– Best solutions are controlled, balanced ventilation systems• Exhaust with motorized damper or ERV/HRV
• Controlled automatically by time, occupancy, or CO2 levels
– Not by humidity
– Higher risk solutions that will be difficult to control• Uncontrolled and unmonitored fresh air intakes on furnaces (barometric damper)
– Usually either open or closed and requires furnace vacuum to operate
– Fresh air is tied to heating or cooling call, not fresh air needs
• Exhaust fans only that rely solely on building leakage for fresh air
– Can work, but need to be controlled and may have to be retrofitted in the future with fresh air intakes
31
HVAC
• HVAC Summary– Indoor air quality is an emerging trend and will be here shortly
• Monitoring systems will dramatically raise awareness levels
– As buildings get tighter and more efficient, IAQ becomes more critical• But also more manageable
– Providing customers IAQ options now is smart business• Provides them with an option to invest now
• Reduces your risk if they measure IAQ later and it is “bad”
– The industry has limited options for maintaining good indoor air quality• Best current option is ventilation, but it needs to be controlled and adjustable
• Other “cleaning technologies” exist, but their in-home effectiveness is a question
– Technology is emerging and staying on top of it will be critical• Find an expert and stay up to date on this
32
Summary
• Building better, tighter and more efficient for less– It isn’t expensive or difficult
– It doesn’t require special windows or other materials
– It WILL save the homeowner money immediately
– It WILL result in a higher quality home
– It WILL allow you to guarantee heating and cooling bills
33
Now what?
• Are you going to implement this stuff?1. No because I don’t think customers will pay for it
2. Probably not because it is too overwhelming
3. Not right now because I am too busy
4. Some of it I think we do a lot of it already
5. Yes I can’t wait to start
• Want to implement, but need help?• We can be your resource to make this happen most cost effectively
– Typically complementing FoE
34