Standard 90.1-2001 applies to the building envelopes (provided the enclosed spaces are at least minimally conditioned with a heating system of at least 3.4 Btu/h/ft2 or a cooling system of at least 5 Btu/h/ft2), HVAC systems, service water heating systems, electric power distribution and metering, electric motors and belt drives, and lighting. Single-family homes, multifamily structures with three or fewer stories above grade, and manufactured houses are not in scope; buildings without fossil fuel or electricity use are not in scope; and equipment and parts of systems that are used primarily for industrial, manufacturing, or commercial purposes are not in scope.
The following buildings are therefore within the scope of Standard 90.1-2001:
- Buildings used primarily for commercial purposes
- Buildings used for industrial purposes, although industrial process systems are excluded from the Standard (and therefore from the 179D tax deduction)
- Multifamily residential buildings of four or more stories, including dormitory buildings
- Buildings that have been converted from other uses to primarily commercial use
- Unconditioned attached or detached garage spaces as referenced by Tables 18.104.22.168 and 22.214.171.124 of Standard 90.1-2001.