This standard defines the roles of and minimum requirements for mechanical and natural ventilation systems, and the building envelope intended to provide acceptable indoor air quality in low-rise residential buildings. This standard applies to spaces intended for human occupancy within single-family houses and multifamily structures of three stories or fewer above grade, including manufactured and modular houses. This standard does not apply to transient housing such as hotels, motels, nursing homes, dormitories or jails.

Units: Dual