Floor Area Ratio

A ratio expressing the relationship between the buildable area (currently built or permitted) and the land on which the property is located. A higher FAR ratio indicates a higher density (i.e. the more area legally permissible to be built on the land).

For example, if a plot of land is 10,000 SF and there is a FAR of 6. The allowable buildable square footage is 60,000 (10,000 x 6).

Calculating Floor Area Ratio (FAR) involves these steps:

  • STEP 1: Find the Buildable Land Area (B), which is the portion of the development site suitable for construction, excluding constraints like public streets and wetlands. Buildable Land Area (B) = (Parcel Width x Parcel Depth) – Area of undevelopable land (if applicable).
  • STEP 2: Determine the Floor Area of each story of the building. Measure the area of each story between the exterior walls, including portions above the ground level before grading.
  • STEP 3: Calculate the Gross Floor Area (G) by summing up the area of each story. Gross Floor Area (G) = Area of 1st Story + Area of 2nd Story… (consider all floors above the ground).
  • STEP 4: Compute the Floor Area Ratio (FAR) by dividing the Gross Floor Area (G) by the Buildable Land Area (B). Floor Area Ratio (FAR) = (G) / (B).

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