Fairfax County, VA Building Setbacks & Zoning: Lot Coverage Limits (2026)

1 of the Zoning Ordinance sets the dimensional standards for the I-I Industrial Institutional District: minimum lot area of 20 acres, minimum front setback of 200 feet (waivable to a lesser distance if the Board approves it to implement a major street improvement, and not required abutting a railroad right-of-way), a maximum building height of 65 feet, a maximum lot coverage of 30 percent, and no floor area ratio requirement. 1 controls bulk through setbacks, height, or floor area ratio rather than a stated coverage cap, so this 30 percent figure applies specifically to I-I-zoned land, not countywide.

Section 9102 defines "Lot Coverage" as the figure produced by dividing the area of a lot occupied by the total horizontal projected surface of all buildings, including covered porches and accessory buildings, by the gross area of the lot. 1 under Section 1108, and building or site plan review confirms coverage calculations before a permit issues. 6; the BZA needs four concurring votes to grant one and must find the strict application would unreasonably restrict use of the property, that the hardship stems from a physical condition of the land or improvements (not one the applicant created), and that the variance would not cause substantial detriment to nearby property.