The handsome home you see above represents the bleeding edge in green design: It’s a “passive house,” designed by Toronto’s Paul Raff Studio. With “automated shades, passive ventilation and mature deciduous trees” it’s meant to stay cool in summer and warm in winter. Say what? How does all that work together?
If you’re fuzzy on exactly what a passive home is, The New York Times just published an excellent infographic highlighting the major design features:
“Passive” housing isn’t a designation you can slap on like LEED certification.* It’s a design philosophy. Passive home building is about installing features that regulate the building’s interior temperature, without requiring active energy systems, such as heaters. Sealing the interior tight is key, features such as triple-thick walls, insulated, tightly-fitting double pane glass with reflective coating, and insulated floors. The orientation of the house itself helps as well, with windows that are shaded from the sun’s natural arc during summer months, but more exposed to sunlight during winter months. The “heart,” as The Times notes, is the heat exchanger, which sucks outside air into the house, and warms it using inside air. It’s incredibly effective: Passive houses require no central heating. Though passive homes are estimated to cost perhaps 15% more to build than regular homes, their energy costs can easily be a whopping 85% lower.
All this sounds simple and irresistible, right? Yet there are only a few thousand passive homes in the world, and almost none of them are in the U.S. But the principles are quickly being disseminated in the building trades–Free Green offers free housing plans which utilize many passive principles.
*Correction: “Passive House” is both a certification and a design philosophy–A German agency has created a passive house designation that functions like LEED, and the certification is available stateside. The house by Paul Raff was designed according to passive principles, but it doesn’t have that formal Passive House designation. Thanks to Lloyd Alter at Treehugger and Preston Koerner of Jetson Green for setting me straight.