This subpart applies to public housing units, except for dwelling units in a mixed-finance project. Public housing is defined as low-income housing, and all necessary appurtenances (e.g., community facilities, public housing offices, day care centers, and laundry rooms) thereto, assisted under the U.S. Housing Act of 1937 (the 1937 Act), other than assistance under section 8 of the 1937 Act.