PHIUS (Passive House Institute US, Inc.) is a non-profit 501(c)(3) organization committed to making high-performance passive building the mainstream market standard. PHIUS trains and certifies professionals, maintains the PHIUS+ climate-specific passive building standard, certifies and quality assures passive buildings, and conducts research to advance high-performance building. Buildings that meet the PHIUS+ standard use 40-60 percent less energy for space conditioning than conventional buildings. PHIUS+ buildings provide superior indoor air quality, resilience during power outages, and an extremely quiet, comfortable indoor environment. Project teams are increasingly adopting passive building principles and the PHIUS+ standard for single-family, multifamily, and commercial construction to achieve Net Zero buildings.

PHIUS’ roots trace back to 2003, when Katrin Klingenberg designed and built her own passive house residence in Urbana, Illinois – the very first home in the United States built to the passive building energy standard. Her experience led her to co-found e-cological Construction Laboratory (e-colab) with builder Mike Kernagis in 2003 as a non-profit affordable housing developer in Urbana, Illinois to further investigate the feasibility of applying passive building principles in the United States. Working in partnership with the City of Urbana, e-colab became a Community Home Development Organization (CHDO) and built single-family passive house projects as affordable housing units.