Typically, a building is divided into different floor areas:

  1. Total Gross Floor Area
  2. Usable Floor Area = Finished + Unfinished Areas
  3. Occupied Floor Area
  4. Finished Floor Area
  5. Unfinished Floor Area

Gross Floor Area.

The total Gross Floor Area is the sum of the gross areas of the several floors of a building or buildings, measured from the exterior faces of exterior walls or from the centerlines of walls separating two buildings.

Usable Floor Area.

Usable floor area is generally the sum of the gross areas of the several floors of a building, measured from the exterior walls or from the center lines of common walls separating two buildings.

Occupied Floor Area.

Typically, this is the Floor area devoted to, or capable of being devoted to, a principal building use and its accessory uses.

Generally, the Occupied Floor Area consists of the Gross Floor Area minus the following:

· Accessory parking and loading spaces and driveways, and maneuvering areas incidental thereto;

· Exterior walls of the building;

· Mechanical equipment, appurtenances, and areas necessary to the operation or maintenance of the building itself, wherever located in the building;

· Restrooms and space for storage and services necessary to the operation and maintenance of the building itself, wherever located in the building;

· Space in a retail store for store management, show windows, and dressing rooms, and for incidental repairs, processing, packaging, and stockroom storage of merchandise for sale on the premises; and

· Incidental storage space for the convenience of tenants.

Finished Floor Area

This is part of the Occupied Floor Area that is devoted and already provides all the finishes like drywall, tiles, carpet, etc. and equipment necessary for someone to live in that space (i.e. kitchen, bathrooms, bedrooms, etc.)  

Unfinished Floor Area

This is part of the Occupied Floor Area that was not finished with materials to create a living environment that meat the living standards. Typically spaces like garages, storage and mechanical rooms are not finished.  This is why, Assessor's Office do not include these spaces when they calculate the property tax.

CityStructure show the Finished, Unfinished Areas as well as the Total Gross Area of a building.