Fabl. Design
Site & Civil / Zoning density limit

Floor area ratio

Definition

The ratio of a building’s total floor area to the area of its lot, often abbreviated FAR. A FAR of 0.5 on a 10,000 sq ft lot allows 5,000 sq ft of floor area.

Floor 1Floor 2Lot area÷Total floor area ÷ lot area = FAR (e.g. 5,000 ÷ 10,000 = 0.5)
Fig. 240 — Floor area ratio: schematic studyNOT TO SCALE

Structural & construction notes

Codes define which spaces count; basements, garages, and attics are sometimes excluded. FAR controls overall bulk, while setbacks and height limits control where that bulk can go.

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