Hobart Net Zero in Massachusetts
Rebuild/DER on Martha's Vineyard
Walls and Roof
super insulated with SIPs and fiberglass, with high efficiency windows, taped and foam sealed.
| Subslab assembly |
slab was pre-existing poured concrete. Was insulaed with 2 inches of foam panels covered with 1.5 inches plywood. |
|---|---|
| Subslab R-value | 7.0 |
| Slab edge assembly |
2 inches of foam paneling on floor to cellar wall . |
| Slab edge R-value | 7.0 |
| 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. |
| Foundation wall R-value | 19.6 |
| Above grade wall assembly |
Same as foundation wall |
| Above grade wall R-value | 19.5 |
| Cathedral ceiling assembly |
10.5 inch foam SIPs for Ranch; |
| Cathedral ceiling R-value | 63.8 |
| Roof Assembly |
6 inch nail base SIPs over 12 inches fiberglass for addition |
| Roof R-value | 65.0 |
Windows and Doors
Window Assembly:
triple pane, triple gasketed tilt and turn inert gas filled windows. PVC frame. hurricane glass on outer pane. Manufacturer is Shuco. custom built.
Door Assembly:
Same as windows; 7 full glass doors
| Average window U-factor | 0.15 |
|---|---|
| Solar Heat Gain Coefficient | 0.44 |
| Visible Light Transmittance | 0.50 |
| Door U-Factor | 0.15 |
| Door Area | 21 sq ft |
Mechanical Systems
| Space cooling - Manufacturer & Model | Daikin same as heating |
|---|---|
| Space heating - Manufacturer & Model | Daikin FFQ12LVJU, Daikin FFQ12LVJU, Daikin FFQ15LVJU, Daikin CDXS18LVJU |
| Domestic hot water - Manufacturer & Model | Steibel Eltron 80 gallon |
| Domestic hot water - capacity | 80 gal |
| Domestic hot water - efficiency | 3 kW |
| Ventilation - Manufacturer & Model | Zender ComfoAir 550 Luxe |
| Lighting Manufacturer and Model | LEDs |
| Lighting Efficiency |
Envelope
| Air Changes per hour, ACH50 | 0.46 ACH50 |
|---|---|
| Air Changes per hour, CFM50 |