Passive House: The Next Big Thing In Green Building?

If you follow the Green Building channel here at EarthTechling, you may have noticed a couple of trends recently. First, LEED certification appears to have infiltrated every corner of the building universe, and second, a number of other green certification systems are on the rise. A number of these certifications, such as Net Zero Energy and National Green Building Standard, were designed, in part, to build on the recognition for green projects that LEED has provided while pushing the green building envelope further.

Among the certifications we’ve been seeing more of recently is Passive House. No two ways about it: when it comes to energy use, Passive House is the most stringent building energy standard in the world. In order to gain certification from Passive House Institute US (PHIUS), a building must use 80 percent less energy than its conventionally constructed equivalent.

Passive House, Salem, Oregon

image via Sarah Evans

Achieving that kind of miserly energy use isn’t easy. In order to “maximize gains, [and] minimize losses,” Passive House-trained designers and builders make use of strategic design and planning; specific climate-based siting and sizing (to maximize passive solar heating and cooling); a super-insulated building envelope; thermal bridge-free detailing; an air-tight building envelope (with open diffusion); advanced windows and doors; energy recovery ventilation systems (to keep fresh air circulating in from the outside, without losing heat); and high efficiency mechanical systems.

We recently had a conversation with Sam Hagerman, President of the Passive House Alliance US, an advocacy organization focused on spreading the good word about Passive House and increasing the number of projects being built to this standard. Hagerman is also the owner of Hammer & Hand, Inc., a residential contracting firm with offices in Portland and Seattle that emphasizes sustainability in the built environment.

EarthTechling (ET): What’s your personal history with Passive House? How did you get interested in building this way?

Sam Hagerman (SH): In 2008 and 2009 my business partner, Daniel Thomas, and I decided to diversify our business more intentionally, including a new and renewed focus on high performance building.  Although we’d been building sustainably since we began Hammer & Hand in 1995, I was worried about issues around high performance building and potential building failures such as sick building syndrome.  Examination of those issues led me to Passive House, and I quickly understood that it was the most developed theory and method for planning and executing a truly high performance buildings.  I saw its laser focus on energy performance as a bridge to a deeper understanding of building science.  And that reinvigorated me as a building professional.  In 2010 I was asked to become part of the Passive House Alliance US and have since been working on the national level to develop and grow this membership-driven organization to help promote adoption of the standard in the field.
Specs, Glasswood Renovation by Hammer & Hand

image copyright EarthTechling

ET: How well known is the Passive House green building standard, and how much, would you say, is it being utilized?

SH: Passive House is a thousand times more well known than utilized at this point, at least in the United States.  Worldwide there are about 10,000 projects certified and 30,000-40,000 built to the standard.  In the US, just over 100 Passive House projects have been built, though hundreds are on the way.  At least 25 projects, some multifamily, are under development right now in the Pacific Northwest.  That’s for new construction.  Retrofitting to the Passive House standard is much more difficult, and the grand total of completed retrofits in US numbers less than 20.

Susan DeFreitas has covered all manner of green technology for EarthTechling since 2009. She is a graduate of Prescott College for the Liberal Arts and the Environment, and has a background in marketing green businesses. Her work on green living has been featured in Yes! Magazine, the Utne Reader and Natural Home.

    • http://www.londonfloorsanding.org.uk/ Victor Sanders

      While the LEED standard is a good standard to follow, to really achieve passive house status, you need at least a net zero energy consumption standard. Obviously, it is easier said than done, but the progress we are making in that area is steadily increasing.
      Victor – http://www.londonfloorsanding.org.uk/

    • http://www.londonfloorsanding.org.uk/ Victor Sanders

      While the LEED standard is a good standard to follow, to really achieve passive house status, you need at least a net zero energy consumption standard. Obviously, it is easier said than done, but the progress we are making in that area is increasing.