Passive House has graduated—and it’s going off to college.
Created in the early 1990s, Passive House started out as a standard for certifying single-family homes. It had three core requirements having to do with modeled heating and cooling demands, modeled total energy demand, and actual airtightness verified by a blower-door test. The standard encouraged superinsulation, passive solar heating, and a maximum amount of square footage per occupant.
That’s all still applicable to homes, but over the years, the original Passive House Institute (PHI) certification system has branched out considerably to offer different requirements for different building types, such as offices, hospitals, schools—even swimming pools. There’s also a considerably different standard in the U.S. administered by Passive House Institute U.S. (PHIUS). But regardless of these differences, all Passive House buildings have to follow the same basic procedures:
insulate to a very high level
eliminate thermal bridges
achieve verified airtightness
take advantage of passive solar heating in cold climates and seasons, and avoid solar heat gain in warm climates and seasons
ventilate properly without undue energy consumption
But it pays off: Passive House buildings are thermally comfortable and use ultra-low amounts of energy. And this can all be done at a 0% to 3% first-cost premium, according to Michael Pulaski, Ph.D., vice president at Thornton Tomasetti.
Hence the attraction for colleges and universities, many of which have made climate commitments—yet still need to build new buildings—and are looking for low-cost ways to reduce that new source of operational carbon in the next few years. Energy and carbon are such paramount concerns that, in some cases, schools are choosing Passive House in place of LEED.
In the following eight case studies, we look at what has attracted colleges and universities to Passive House, and we document some of the complexities and some of the problem solving required for certifying to Passive House standards in an institutional setting.