Stafford County, VA Accessory Structures: ADU Rules (2026)

Section 28-25 defines "dwelling, accessory" as an ancillary dwelling unit limited to uses such as a family member apartment, an occasional-visit guest house, or maid's quarters, and it sets five conditions the unit must meet. It cannot exceed 25 percent of the total gross floor area of the principal dwelling, and only one accessory dwelling is permitted per lot. Where the accessory unit sits within the principal dwelling itself, its entry and design must be arranged so the building still reads as a one-family residence from the outside.

The accessory dwelling must carry the same street address as the principal dwelling, tying it administratively to the main house rather than functioning as an independently addressed unit, and the definition specifically excludes a carriage house, which Stafford regulates as its own dwelling type with a different address and access from an alley. 1 under § 28-35 lists "accessory dwelling" as a use permitted by right in districts such as A-1 Agricultural and A-2 Rural Residential, so a qualifying unit does not need a conditional use permit in those districts, though it must still meet the district's setback, height and lot-coverage standards under § 28-24.