Project Subtitle:
Project Description:
This project involves taking a single family home that was built in the 1970s and transforming it into a super-insulated high effeciency home that is Net-Zero Ready
Building Type Summary:
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Occupancy Type and Details:
Owner-occupied
Conditioned Floor Area:
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Multiple buildings?:
Total floor area of project (all buildings):
Historic?:
Completion date:
Site description:
A well drained site in a residential area
Materials:
The exterior walls of this building consisted of vinyl siding that was placed on top of original cedar shakes. The vinyl siding was removed and installed on another house and the cedar shakes were removed and re-stained and replaced on original house. Before cedar shake siding was re-applied, 4 inches of polyisocyanurate insulation was applied over the water-resistive barrier (house wrap with taped seams). Then 5/8 " plywood was applied and finally a drainable housewrap.
Energy Highlights:
Two ductless minisplits are providing all heating and cooling needs
Electric Utility Company:
Subslab assembly:
n/a
Slab edge assembly:
Since this was a retrofit, could not insulate slab edge. I stead slab was insulated on top with 2 inches of ridged foam and sheathed with 3/4" t&g plywood
Foundation wall assembly:
4 inches of polyiso, and 4 inches of fiberglass batts on inside of foundation wall. All joints in polyiso were sealed.
Above grade wall assembly:
Existing 2x4 walls with 1/2
Flat attic assembly:
1/2" drywall, 5" blown-in cellulose (existing), 2" polyiso sheathing, 12" blown-in cellulose, perimeter spray foamed for air sealing
Cathedral ceiling assembly:
1/2" drywall, Smart-poly membrane, 5-1/2" dense pack cellulose, 5-1/2" closed cell foam
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Domestic hot water - Manufacturer & Model:
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Ventilation - Manufacturer & Model:
Process:
Being an environmental scientist and a carpenter/framer/builder for past 30 years, a natural design for my own home is a Net Zero Ready. I designed the house after taking Heat Spring course
Design for Adaptability:
Durability
Energy Modeling Software:
Marc Rosenbaum copyright 2012
Outcome of project goals:
Window details difficult; would have done outside mounting and have had drainage wrap double as WRB
Discrepancies:
TBD
Finances Description:
This house was purchased for 240K
Total Cost of Project:
Construction hard cost:
Gross Cost of Renewable Energy System:
Value of Tax Credits for renewable energy systems:
Net Cost of renewable energy systems:
Federal incentives:
TBD
Special architectural measures:
All windows were replaced with triple pane windows and north facing glazing was minimized while optimizing south facing glazing
Energy Strategies:
The thermal envelope of this building was taken to R-20 basement floors, R-40 basement walls, R-40 exterior walls, R-60 cathedral ceilings, R-70 flat ceilings from a 1970s code house
Energy Use and Production Documentation:
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Project Photos:
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Scope Description:
This was a retrofit that involved stripping existing house to the studs, removing all old plumbing and heating, and re-wiring. The exterior was stripped to the plywood sheathing and the cedar shakes that were removed are being re-stained and put back on building (lots of work, but worth it!)
Site conditions:
Summary of enclosure strategy/description:
Increased R-values of basement floors to 20, basement walls to 40, exterior walls to 40, cathedral ceilings to 60, and flat ceilings to 70
Roof Assembly:
n/a
Window Description:
South facing: Weather Shield, triple pane with Cardinal 180, clear,180: SHGC = 0.56
All others, Marvin Integrity, triple pane with Cardinal 282, clear, 282: SHGC = 0.32
Door Description:
Therma-Tru solid core
Mechanical Equipment Installation Details and Comments:
A blower door test will be performed when house gets near completion. All penetrations were sealed from inside and outside. Condensing dryer and re-circulating range hood preclude big holes in envelope