Assignable area for a building as a whole is calculated by summing the assignable area of the individual rooms in the building. Refer to Appendix C, Building Area Overview, and Appendix D, Definitions Checklist, of the Facilities Inventory Guide for further discussion and definitions of Assignable Area.

For leased facilities, when actual assignable area measurements are not available, net rentable area may be used to record assignable area and basic gross area.