News Analysis

The Two Passive Houses: A Comparison

PHIUS and PHI certifications have been considered “separate but equal” in the U.S. marketplace for years. But are they really equivalent?

It was a long time coming. After years of turmoil over whether Passive House should be more flexible, in 2011 the international Passive House Institute (PHI) issued a judgment about Passive House Institute U.S. (PHIUS): the American institute could no longer certify Passive House projects to the international standard or administer international Passive House accreditation exams.

Throughout its eight years of going it alone, PHIUS has devised a completely different standard, offers a parallel professional accreditation program—Certified Passive House Consultant program—and has developed its own modeling software. Yet, among the uninitiated, Passive House is Passive House. The vast majority of people don’t even know there are two separate certifications—let alone how they compare.

Published August 6, 2019

Melton, P. (2019, August 6). The Two Passive Houses: A Comparison. Retrieved from