Aggressively Passive: Building Homes to the Passive House Standard

Enlarge Image Image Gallery Catherine O’Neill’s California home is the first U.S. retrofit to be certified by the Passive House Institute U.S. Photo By Ned Bonzi

Imagine spending a long Illinois winter in a cozy house with no cold corners or drafts—and heating bills half the norm—or sailing through a sultry Louisiana summer in cool comfort with bills that cost a fraction of the neighbors’. Passive House, the latest set of building standards sweeping North America, uses seven simple principles to make these housing dreams come true.

Passive Houses are so well designed, insulated, sealed and ventilated that they require as little as 10 percent of the energy standard homes use for heating, cooling and lighting. A tight envelope (roof, exterior walls and floor) and thick, heavily insulated walls keep winter cold and summer heat at bay with little reliance on furnaces and air conditioners. In winter, Passive Houses hold in heat from the sun, inhabitants’ bodies, lights and appliances. In summer, they keep cool air in and hot air out, though additional cooling may be needed in very hot, humid climates. Energy-recovery ventilators (ERVs) circulate fresh air for even temperatures and humidity.

Though the movement traces its roots to the American superinsulated house movement of the 1970s, the Passive House principles were further developed and codified by German professors Wolfgang Feist and Bo Adamson in the 1980s and 1990s. Using the standards of the Passivhaus Institut (PHI) founded by Feist in 1996, thousands of European homes have been built or remodeled, and many provinces and cities require projects built with public monies to achieve PHI certification. Architect Katrin Klingenberg brought the Passive House movement to the United States, co-founding the Passive House Institute United States (PHIUS) with builder Mike Kernagis in 2008. Close to 60 Passive House projects have been completed or are underway around the country.

Selfish Altruists 

In Europe, the Passivhaus Institut has worked out many of the system’s kinks, but the United States encompasses a different range of climates, aesthetic tastes, and financial and property practices. Every U.S. Passive House breaks new ground. With Passive House construction costs at 6 to 15 percent above average, early adopters must be committed to long-term, deep energy conservation and be willing to work out the bugs for the rest of us.