Introduction and Instructions
Space needed to accommodate circulation among programmed spaces varies
significantly with each facility's specific design. Determining appropriate internal
circulation factors depends upon many issues, such as building configuration,
average size and depth of spaces, and the general design of the area (i.e.,
"compressed" versus "spacious"). Based on a study of completed courthouse
designs, the Guide provides specific values to estimate circulation space
requirements for various offices and functional areas of a courthouse. Please refer
to the appropriate chapter for specific circulation criteria.
The NSF criteria in the Guide also do not account for building support spaces that
are included in the building gross area. The building gross areas include public
circulation, partitions, mechanical and electrical rooms and risers, elevator shafts,
stairs, public corridors and lobbies, public toilets, internal and external wall
thicknesses, and other areas.
To help clarify these terms, Figure I.1 illustrates the "net," "occupiable," and
"gross" areas provided on courtroom floors.
Estimating Total Gross Area
For planning purposes, a useful general internal circulation factor is 20%. To
account for circulation among programmed spaces, multiply the NSF by 1.20,
which provides an estimate of the facility's "occupiable area."
The "occupiable area" typically accounts for 67% to 72% of the total gross area
of court facilities. To calculate the total gross area, divide the occupiable area by
0.67 to 0.72. The resulting value is expressed in gross square feet (GSF) or gross
square meters (Gm2).