Posted on November 13, 2014 by Mike Steffen in Guest Blogs
In Portland’s western suburbs, a structure is on the rise that could change the face of affordable housing in America. Situated adjacent to the Orenco Station light rail transit stop in Hillsboro, Oregon, the Orchards at Orenco will provide 57 units of housing. The project sponsor, REACH Community Development, is aiming to achieve PassivhausA residential building construction standard requiring very low levels of air leakage, very high levels of insulation, and windows with a very low U-factor. Developed in the early 1990s by Bo Adamson and Wolfgang Feist, the standard is now promoted by the Passivhaus Institut in Darmstadt, Germany. To meet the standard, a home must have an infiltration rate no greater than 0.60 AC/H @ 50 pascals, a maximum annual heating energy use of 15 kWh per square meter (4,755 Btu per square foot), a maximum annual cooling energy use of 15 kWh per square meter (1.39 kWh per square foot), and maximum source energy use for all purposes of 120 kWh per square meter (11.1 kWh per square foot). The standard recommends, but does not require, a maximum design heating load of 10 W per square meter and windows with a maximum U-factor of 0.14. The Passivhaus standard was developed for buildings in central and northern Europe; efforts are underway to clarify the best techniques to achieve the standard for buildings in hot climates. certification. When complete in the spring of 2015, Orchards at Orenco is slated to be the largest Passivhaus-certified building in North America.