Zoning Tools / FAR Calculator

Floor Area Ratio (FAR) Calculator

Floor Area Ratio (FAR) is a ratio used in urban planning and development to assess the amount of usable floor space relative to the total area of a lot. It is am important part of zoning regulations and building codes and is used to control the density of buildings.

FAR Calculator

FAR Forumla

Floor area ratio is calculated by dividing the total floor area of a building by the total area of the lot it is built on.

FAR Variables

Total Floor Area: This is the sum of the floor area within the building envelope. This includes all the usable space in the building and excludes unusable areas like basements, parking garages, staircases, etc.

Lot Area: This is the total area of the lot on which the building is constructed. It includes the area occupied by the building and the surrounding open spaces within the lot boundaries.

FAR Explained

In practical terms, a higher FAR means a higher density. For instance, a skyscraper on a small plot would have a high FAR, while a single-story building on a large plot would have a low FAR.

FAR is used in zoning regulations to limit building densities. It helps to prevent overcrowding and ensures that infrastructure and services such as roads, water supply, and sewage systems are not overwhelmed.

Planners also use FAR to maintain the character and aesthetics of an area, by preventing buildings that are too large or out of scale with their surroundings.

For developers and architects, understanding the FAR is crucial for maximizing the development potential of a plot.


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