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Last edited 17 Sep 2018
Floor area ratio
The floor area ratio (FAR), also known as the plot ratio, is a measure of the total permitted floor area of a building, in relation to the total area of the lot (or plot) on which the building stands:
A higher ratio indicates a higher-density environment.
The concept emerged in Europe in the 19th century, and was then taken up in the USA in the 20th century as a form of zoning control for rapidly developing cities. FAR is now often used by urban planners, particularly in the USA, for assessing, or restricting, planning permissions, setting a limit on the 'load factor' generated by new developments, beyond which undue stress is placed on a city and its infrastructure.
The same FAR value can be achieved by buildings with varying numbers of storeys. For example:
1,000 sq. m building with one storey / 4,000 sq. m lot = 0.25
500 sq. m building with two storeys / 4,000 sq. m lot = 0.25
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