Curbed National (10/08/15) Sisson, Patrick
The world's greenest home, the Karuna House in Newberg, Ore., has earned an unprecedented number of certifications and awards, including Passive House, MINERGIE, LEED Platinum, U.S. Department of Energy Zero Energy Ready Home, and Earth Advantage Platinum. The building's energy needs are all provided by a photovoltaic array of less than 10 kilowatts. Designed by Holst Architecture and built by Hammer & Hand, the $2 million, 3,500-square-foot home has annual energy bills of only $50. By applying passive solar design, super-efficient insulation, and a sophisticated understanding of how air, heat, and moisture work inside the building, tight interiors now have better airflow without the condensation and poor indoor air quality of earlier attempts at building seamless building envelopes. Improved modeling and construction techniques also allow designers a free hand with the exterior of homes. "You can make a passive house now that looks like anything on the cover of a high-design architecture magazine," says Hammer and Hand's Zachary Semke. The house used a 12-inch-thick section of EPS geofoam laid on top of gravel to thermally isolate the building from the ground. Walls feature layers of materials making them air- and water-tight. Doors have series of gaskets and windows are triple glazed with motorized shades to balance solar gain. "The point of this was to show that green design and architecture can be synonymous with good design," Semke says.