Floor Area Ratio

The ratio of a building's total floor area to the size of the lot it occupies, used as a zoning tool to control building density and bulk.

What is Floor Area Ratio?

Floor area ratio (FAR) is a zoning metric that expresses the relationship between a building's total gross floor area and the total area of the lot on which it sits. It is calculated by dividing the building's total floor area by the lot area. For example, a FAR of 2.0 on a 10,000-square-foot lot means the building can contain up to 20,000 square feet of floor area — distributed across one or more stories.

How FAR Works

FAR controls the overall bulk and intensity of development without dictating building form. A FAR of 2.0 could produce a two-story building covering the entire lot, a four-story building covering half the lot, or an eight-story building covering a quarter of the lot. This flexibility allows FAR to work alongside other standards like setbacks, height limits, and lot coverage to shape the built environment.

FAR and Development Feasibility

For developers, FAR is one of the most important zoning metrics because it directly determines the maximum leasable or salable area a project can achieve on a given site. Higher FAR means more buildable area and, generally, more revenue potential. FAR is a primary factor in land valuation for development sites.

FAR Bonuses and Incentives

Many municipalities offer FAR bonuses — additional floor area above the base FAR — in exchange for providing public benefits such as affordable housing, publicly accessible open space, LEED certification, or transit improvements. Understanding available bonus FAR provisions can significantly affect the financial feasibility of a project.