3.2.2 Net Assignable Area (Net Assignable Square Feet—NASF)
(See figure 3-3)
- Definition. The sum of all areas on all floors of a building
assigned to, or available for assignment to, an occupant or specific use.
- Basis for Measurement. Net Assignable Area is computed by physically
measuring or scaling measurements from the inside faces of surfaces that
form the boundaries of the designated areas. Exclude areas having less than
a 3-foot clear ceiling height unless the criteria of a separate structure
are met. (See section 2.3, What to Include in a Building Inventory.)
Measured in terms of Net Assignable Square Feet (NASF),
NASF = Sum of Areas Designated by the 10 Assignable Major Space Use Categories
- Description. Included should be space subdivisions of the 10
major space use categories for assignable space—classrooms, labs, offices,
study facilities, special use, general use, support, health care, residential,
and unclassified—that are used to accomplish the institution’s
- Limitations. Deductions should not be made for necessary building
columns and projections. These small areas are excluded as they represent
an insignificant percentage of the total area of an average-sized space.
Capturing their area would be unduly burdensome relative to the very small
contribution they would make toward precision. Areas defined as building
service, circulation, mechanical, and structural should not be included.
Figure 3-3. Net Assignable Area of a building by floor