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PASSIVE HOUSE RETREAT
This private retirement residence located in an oceanside community features high performance in a small package. The owners desired exceptional performance with a modern aesthetic, combined in a house no larger than their needs. The answer was a simple gable roofed structure, designed to the Passive House Standard, and rightsized for the couple's lifestyle.
High R-values in the home, including R-44 walls, R-50 slab, R-60 roof, U-Value: 0.13 windows, and exceptional air sealing mean that only about one-tenth of the energy is needed for heating when compared to the requirements of a conventionally constructed home.
In addition to the very small heating system (a single ducted air source heat pump), the house also incorporates a heat recovery ventilator to maintain excellent indoor air quality with minimal energy expense.
Recent actual performance for the trailing twelve months is an average of 412 kWh per month for all energy consumption. A small 4.1kW solar electric system would generate more than enough energy to offset all consumption and make the home net zero energy.
| PERFORMANCE DATA |
| Heat Demand |
4.03 kBTU/(ft2yr) |
| Air Tightness |
0.75 ACH50 (first test) |
| Primary Energy |
30.9 kBTU/(ft2yr) |
| Cooling Demand |
2.75 kBTU/(ft2yr) |
| Heat Load |
5.58 BTU/(ft2hr) |
| Cooling Load |
5.31 BTU/(ft2hr) |
| CONSTRUCTION |
| Framing |
Double stud wood frame, 24" on center, 11" wall assembly, no thermal bridging |
| Windows & Doors |
U Value: 0.13, SHGC: 0.60 |
| Insulation |
Medium density spray foam and cellulose
R-44 walls
R-50 slab
R-60 roof
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| MECHANICAL |
| Heating/Cooling |
Mitsubishi ducted air source heat pump
(HSPF 10, SEER 15.5)
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| Ventilation with Heat Recovery |
Zehnder Comfoair HRV |
| Hot Water |
GE GeoSpring heat pump hot water heater |
| CERTIFICATIONS |
| LEED Gold |
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| ENERGY STAR |
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