Project Subtitle:
Project Description:
This is a rebuild and Deep Energy Retrofit of a 1970's ranch with a full poured cement cellar, with a 1990's addition on concrete piers. The location, within the coastal zone, precluded any expansion of the footprint, but expansion upward was allowed. The original ranch was torn down to the first floor deck, preserving the cellar, and the addition was completely gutted, but left standing. The ranch was rebuilt into a two story house with SIPs, the addition was insulated, top, sides and bottom, with exterior nail base SIPs and interior fiberglass and the cellar was sealed with spray foam, foam panels and fiberglass. High efficiency windows, ventillation, minisplits, HP water heater, energy star appliances, LEDs and a monitored 5.36 KW PV system complete the package. The house is totally electric, and has a Net electric meter, tied to the grid. The HERS rating is 22.
Building Type Summary:
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Occupancy Type and Details:
Owner occupied; 2 occupants full time. Occasional house guests: 4 for 2-3 weeks per year
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Multiple buildings?:
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Site description:
The house is on a ~.85 acre lot on a peninsula including a tidal salt marsh and on the edge of a salt pond, totally within the coastal zone.
Materials:
As it is in the coastal zone, no increase in footprint was allowed; a variance was obtained for a slight increase in height, to allow a second floor. Local regulations limit the amount of fertilizer which can be applied per year; we actually apply none, using native plants. The existing cellar and pilings were preserved and minimal excavation was done to install a nitrogen reduction septic system.
Energy Highlights:
4 minisplit air source heat pumps provide heat. Steibel Eltron heat DHW.
LCA Description:
No
HERS Index:
Annual renewable energy generated:
Electric Utility Company:
Gas Utility Company:
Datasets and Utility Bills sources and reliability:
Locus Energy LGate-101E monitoring system.
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Energy Storage type:
None yet. Ordered Tesla 10 kW storage battery, but has not yet been delivered.
CHP System Description:
NA
Subslab assembly:
slab was pre-existing poured concrete. Was insulaed with 2 inches of foam panels covered with 1.5 inches plywood.
Slab edge assembly:
2 inches of foam paneling on floor to cellar wall .
Foundation wall assembly:
preexisting poured concrete. Covered with 3 inches of foam panels, 3.5 inches of fiberglass and .75 inches of plywood. Rim joists were spray foamed to 4 inches.
Above grade wall assembly:
Same as foundation wall
Cathedral ceiling assembly:
10.5 inch foam SIPs for Ranch;
Door Area:
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Process:
Attended NZE course from NESEA; designed house as capstone project
Other Software tools:
Marc Rosenbaum custom software
Finances Description:
self financed
Total Cost of Project:
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Federal incentives:
3000
State incentives:
7000
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Advice:
Get financing before starting the project
Special architectural measures:
South facing window area, along long axis of house, was maximized; other exposures were minimized. All windows have overhangs which minimize heat gain in summer but allow maximum heat gain in winter. Window SHGC is 0.440, U factor is 0.150. Windows were installed with foam and taped around the edges. Windows are hurricane glassed. House walls are about R-45, roof is R-65. The ranch is build with SIPs and the (gutted) addition is sheathed with nail-base SIPs. Cellar was foam paneled and the rim joists were spray foamed. Blower door testing revealed it met the Passiv Haus standard for air infiltration.
Energy Strategies:
The house is super insulated, with the building envelope extremely well sealed. The long axis of the house faces south and window area is maximized, with overhangs to take advantage of solar insolation. All appliances are Energy Star or use minimal energy for their type.
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Scope Description:
Original 1970's single story ranch (with full cellar) with 1990's one room addition with porch, on pilings. Ranch was demolished to first floor deck, cellar was preserved. One room addition was gutted to studs, floor and roof, and porch removed.
Site conditions:
Renewable Energy Sources:
Other Purchased Fuels Description:
No
Storage Strategies & System Details:
Will be wired to provide power for limited heat, ventilation, lighting and refrigeration until PV system can recharge the battery.
Summary of enclosure strategy/description:
super insulated with SIPs and fiberglass, with high efficiency windows, taped and foam sealed.
Roof Assembly:
6 inch nail base SIPs over 12 inches fiberglass for addition
Roof R-value:
Window Description:
triple pane, triple gasketed tilt and turn inert gas filled windows. PVC frame. hurricane glass on outer pane. Manufacturer is Shuco. custom built.
Door Description:
Same as windows; 7 full glass doors
Number of Bedrooms:
Team Members:
Local builder