Seattle, WA - 26 February, 2013 - After a second attempt, last week Dwell Development
, an award winning Seattle-based design+build boutique firm, achieved the results needed to meet the strict standards of Passivhaus. Passivhaus is an ultra-low energy standard that outperforms LEED in terms of energy efficiency. According to the Passivhaus Institut
, homes that meet this standard acheive thermal comfort by postheating or postcooling of the fresh air mass without a need for recirculated air. In layman terms, that translates to getting a 90% off coupon on your space heating and cooling bill.
Last week's blower door test resulted in 0.58 ACH50, or .58 air changes per hour under 50 pascals of pressure. In comparison, a regular code home changes air about 7 x per hour under 50 pascals of pressure. Working with consulting and design practice Brute Force Collaborative
, the construction of the home began in September 2012 as one of only a handful of in-fill spec projects seeking Passivhaus certification in the US, and the only one in the Pacific Northwest to date.
"We made the committment to building a Passivhaus on spec because we believe so strongly in creating energy efficient homes and keeping them affordable" stated Anthony Maschmedt, principal of Dwell Development. "its paying off now...the home pre-sold in November 2012, in the early framing stage of the project".
The first blower door test, which took place at the end of January, resulted in a reading of 1.62 ACH50. Remedies that brought in the successful reading included re-installing windows, reapplying the exterior waterproof air barrier, and taping or sealing tiny holes where joints meet. Tadashi Shiga of Evergreen Certified
was the 3rd party verifier - he is the only verifier in Washinton State certified to verify Passivhaus.
See this 7-part series of short videos showing the events as they unveiled last week, here