Floor area and building coverage diagrams

For projects with new construction that are adding floor area (either Floor Area Limit (FAL) or Gross Floor Area (GFA)) and/or building coverage, the Planning Division requires diagrams to confirm the calculation of floor area and building coverage. This requirement applies to both Planning and Building proposals. These diagrams allow the listed square footages to be confirmed for accuracy, as shown in the following example:

Floor area/building coverage calculation example

Diagram specifications

• The calculation diagrams should at minimum be no smaller than half the scale of the equivalent floor plans. For example, if your floor plans are at 1/4" = 1' scale, the associated calculation diagrams can be no less than 1/8" = 1' scale.
• The calculation diagrams should be overlaid on the proposed floor plans (i.e., walls and stairs must be visible), with each floor divided into a minimum number of discrete polygons, listing the length, width, and area of each. For curves or other non-rectangular shapes, list the method of area calculation.
• On the ground floor calculation diagram:
  • Use a unique area calculation box (or combination of boxes) for any garage or carport space. 
  • Show area calculation boxes for covered porches, trellises, or any other area that counts as building coverage but not floor area. Shade these building coverage boxes with a distinct hatching or other unique pattern.

Floor Area Limit (FAL), Gross Floor Area (GFA), and Building Coverage Defined

Floor Area Limit (FAL) is used in single-family and R-2 zoning districts, and establishes the maximum amount of square footage permitted to build on a property. FAL is the square footage of all above-ground levels of the house, accessory buildings, and garages or carports. For more details, please see Zoning Ordinance Sections 16.04.313 (“Floor area”) and 16.04.314 (“Floor area limit”).

Gross Floor Area (GFA) establishes how the maximum amount of floor area is calculated in all other districts of the city. GFA does not include areas devoted to covered parking or enclosures solely for trash and recycling, but does include a number of areas that FAL does not count. For more details, please see Zoning Ordinance Section 16.04.325 (“Gross floor area”).

Building coverage (or “land coverage”) is the percentage of the project site permitted to be covered by buildings, as measured from the ground upward, exclusive of any eave not in excess of six feet. Building coverage can be considered the footprint of all buildings on the site. Building coverage includes all structures with roofs, including semi-solid roofs such as trellises and arbors. Building coverage is regulated in addition to FAL/GFA in many zoning districts. For more details, please see Zoning Ordinance Section 16.04.120 ("Building coverage").