Melpet Farm Residences, Affordable Net Zero Ready
Walls and Roof
Our approach was to balance the building envelope performance with PV production, program and cost. Understanding the PV capacity of the roof surfaces facing south, the occupants and the budget constraints provided the parameters for our design.
| Subslab assembly |
2 layers of 1.5 inch type IX EPS Insulation |
|---|---|
| Subslab R-value | 14.0 |
| Slab edge assembly |
.5 inch cement based filler over 2.5 inch type IX EPS Insulation |
| Slab edge R-value | 12.0 |
| Foundation wall assembly |
2 layers of 1.5 inch type IX EPS Insulation |
| Foundation wall R-value | 14.0 |
| Above grade wall assembly |
Starting below the sill plate: continuous 1.5 inch sealant impregnated foam tape and 3.5 foam sill sealer, 2 x 6 wood stud walls insulated with dense packed cellulose, .5 inch zip wall taped covered by 1.5 inch foil face polyisocyanurate with taped joints, vertical 1 x 4 furring at 16" oc, and fiber cement siding. |
| Above grade wall R-value | 30.0 |
| Flat attic assembly |
Loose fill cellulose insulation |
| Flat attic R-value | 50.0 |
| Roof Assembly |
Asphalt shingles over 5/8" zip sheathing with taped joints. |
Windows and Doors
Window Assembly:
Paradigm 8381 Vinyl Triple Pane
| Average window U-factor | 0.24 |
|---|---|
| Solar Heat Gain Coefficient | 0.23 |
| Visible Light Transmittance | 0.38 |
Mechanical Systems
| Space cooling - Manufacturer & Model | AOUA72RLBV |
|---|---|
| Space cooling - capacity | 22 kW |
| Space heating - Manufacturer & Model | Fujitsu VRF AOUA72RLBV |
| Space heating - capacity | 25 kW |
| Domestic hot water - Manufacturer & Model | State Hybrid Heat Pump Hot Water Heater |
| Domestic hot water - capacity | 50 gal |
| Domestic hot water - efficiency | 3 kW |
| Ventilation - Manufacturer & Model | 475 Lunos E2, Panasonic Whisper Green |
| Lighting Manufacturer and Model | |
| Lighting Efficiency | |
| Mechanical Equipment Installation Details and Comments |
Daily review by Owners Construction Representative, selected because he has knowledge of energy efficiency construction. Site visits made by Clear Result to perform quality control and blower door testing to evaluate airtightness. |
Envelope
| Air Changes per hour, ACH50 | 1.06 ACH50 |
|---|---|
| Air Changes per hour, CFM50 |