You may have seen the term Passive House used here and there, but since it’s a quite complex and often misunderstood approach to construction, we wanted to write a two-part series diving more deeply into it for our readers. Full disclosure — Living Shelter Architects is supportive of the increasing interest in Passive House and we even have a Passive House-certified architect on our team, Troy Howe. If you still have questions after reading, you are always welcome to contact us!
What is Passive House?
Passive House is the most stringent energy conservation standard for the assembly of building envelopes in the world. Passive House offers the opportunity for buildings to be resilient, healthy, economical, and environmentally-friendly.
Despite the word “house” in its name, Passive House is not just for residential buildings. The German term PassivHaus actually means “Passive Building” in German. Since residential buildings are where this rigorous building standard was first employed, English-speaking countries translated the German term to Passive House.
How Does Passive House Construction Differ From Regular Construction?
The seminal building elements in a Passive House are:
a continuous insulation envelope
a continuous air barrier
thermal bridge free detailing
high performance windows and
a heat recovery ventilator
These are essential to achieving much lower energy consumption than standard construction. Standard construction typically does not have either of these because it is only targeting the code minimums allowed.
What are the benefits of Passive House?
Very low energy consumption with the potential of being off-the-grid with the addition of green energy systems, such as solar panels.
Very high indoor air quality by substantially reducing unintended air flow through the building envelope and focusing all air flow at one intended location through an HRV with air filters.
Substantial reduction or elimination of moisture in the building envelope that may cause mold and mildew.
Elimination of the heat stratification in typical homes. The air temperature at the ceiling is almost the same as at the floor.
Are Passive House Homes More Expensive To Build?
Passive House homes may have a 10% - 15% additional cost over standard construction. This additional cost significantly reduces when a Passive House experienced builder is engaged to build the home. There is also a breakeven point as buildings get larger where the additional cost is the same as standard costs.
Can You Turn An Existing Home Into A Passive Home?
Yes, you can! The PassivHaus Institute in Germany recognized the significant need to upgrade the existing building stock. They accounted for this in the Passive House Planning Package (PHPP) calling it the EnerPHit certification. However, the EnerPHit approach does not achieve the stringent Passive House standard of new construction.
Stay tuned for Part 2 of our Passive House series, which will cover materials, why PH standards alone don’t automatically mean a healthy home, and how Living Shelter combines healthy materials with PH assembly to create healthy buildings. And, as always, contact us if you have any questions or are considering a project. We’d love to help!