Passive house (Passivhaus) is a voluntary building performance standard for very high energy efficiency and thermal comfort that substantially reduces a building’s carbon footprint. Buildings certified to the standard are ultra-low energy and typically require very little energy for space heating or cooling. The approach is used for housing and for non-residential buildings such as offices, schools, kindergartens and healthcare facilities. Energy efficiency is integral to architectural design rather than an add-on. Although most common in new construction, the principles are also applied in deep renovations (see EnerPHit).
As of January 2025, projects certified by the Passive House Institute (PHI) comprise over 47,400 units with about 4.32 million m² of treated floor area (TFA) worldwide; the public PHI database lists nearly 6,000 projects. In North America, the Passive House Institute US (PHIUS) reported 500+ total certified projects and ~1.6 million ft² certified in 2024 alone, with 4.4 million ft² design-certified that year. While early adoption concentrated in German-speaking countries and Scandinavia, certified projects are now documented across diverse climate zones, including hot-humid and tropical regions.