Quality Approved Passive House
October 14th, 2010 by Tim Delhey Eian
We received the certificate from PHIUS today. The Passive House in the Woods is now officially a Quality Approved Passive House.
Here is a quick list of it’s key performance data in reference to Passive House limits:
- Heating Load: 10.6 kWh per m2 living area and year [3.36 kBTU/ft2yr]
(limit: 15 kWh or 4.75 kBTU); about 30% less than allowed - Air Tightness: 0.25 ACH50 in reference to the building’s volume
(limit: 0.6 ACH50); almost 60% better than allowed - Source Energy Consumption: 106 kWh per m2 living area and year [33.6 kBTU/ft2yr]
(limit: 120 kWh or 38.05 kBTU)* - CO2 Emissions: 16.5 kg per m2 living area and year;
CO2 Emissions avoided with solar PV system: 16.9 kg per m2 living area and year.
Therefore the building becomes CO2 neutral for operation.
*) The design was made for a 2 person household, which lowers this number to 65 kWh, or 20.6 kBTU
Calculations are based on the Passive House Planning Package 2007 model.
Congratulations an effort worth celebrating!
Congrats Tim! It’s a beautiful project.
Mike
Impressive house design! How does passive solar heating figure into the design concept? Is the house oriented toward south? It doesn’t appear from the photos that there is a great amount of glazing intended for solar gain. Do the huge energy savings rely on direct solar gain w/ interior mass for thermal storage? …or more on super insulation and tight construction?
JW,
One of the basic concepts of Passive House design is to minimize losses and maximize gains. In short this means that insulation and air-tightness work together to limit the amount of energy needed to condition the home. Passive solar heat gains are then utilized to help make up the difference. The building is oriented perfectly south and the south facade generously fenestrated. The glazing is specifically selected to allow for high solar heat gain but offer a high insulating value as well. In summary, the Passive House is more of a retention model, than it is a storage or absorption model. It’s all about keeping in that precious energy—sort of like a thick winter coat.