What's a Passive House? Here's a good simple explanation

via TreeHugger by Lloyd Alter

What is a a Passive House? One critic of Passive House design called it “a single metric ego driven enterprise that satisfies the architect's need for checking boxes, and the energy nerd's obsession with BTUs.” But over at Curbed, Barbara Eldridge writes a terrific explanation of what Passive House construction is, and not once mentions BTUs or CFM or ACH or HRV. This is difficult, since so many Passive House people actually are energy nerds. And while Passive House is very much a process, what matters to the public are the end results.

She talks to TreeHugger regular Bronwyn Barry and writes:

"Passive house is the radical notion that you can reliably and consistently design a building that works for humans," explained Barry. "It’s a comfort standard and a methodology."

Essentially, a passive house is designed to be extremely energy-efficient so that it doesn’t take a lot of power to heat or cool. To be designated as a passive house, a building must embody a set of specific best practices that seal it from outside temperatures while maintaining a stable inside temperature and high air quality.

And that is as close to math as you get.

"It’s sort of like building a thermos," said Ken Levenson, "but it’s a thermos with really good ventilation." When you want a space to naturally maintain its temperature—whether it’s as small as a thermos or as large as a home—you’re going to be following many of the same rules. Passive homes need to be air-tight, have continuous insulation, triple-paned windows, and a great system for controlling air quality.

Bronwyn and Ken then point out what is probably the most important benefit to occupants in Passive House designs: Comfort. They also note that they are not built all that differently from conventional buildings, don’t cost a lot more, and don’t have to look weird, although they can be what Bronwyn hashtagged as #BBB, or Boxy But Beautiful.”