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

Roanoke County Code § 30-82-1 lets an accessory apartment attach to a detached single-family residence by right, without a special use permit, so long as the general standards in § 30-82-1(B) are met. An apartment built inside an accessory structure on the lot needs the parcel to already meet the underlying zoning district's minimum lot size and the accessory building to meet every zoning requirement that applies to a principal building; if it can't clear those two tests, the owner must instead get a special use permit under § 30-19.

Size is capped both ways: § 30-82-1(B)3 limits the finished floor area to no more than 50 percent of the principal dwelling's finished floor area, and in no case can the apartment exceed 1,500 square feet, while § 30-82-1(B)6 sets a 300-square-foot floor. The apartment must add one parking space beyond what the principal dwelling already requires, and no separate driveway is allowed except where another subsection permits one, per § 30-82-1(B)7. Health department approval of the sewage disposal method has to reach the county before it will issue the building permit, under § 30-82-1(B)8.

In the C-1 and C-2 commercial districts, § 30-82-1(C) lets an accessory apartment ride along with a civic, office, commercial or industrial use, provided that use still occupies at least half the site's gross floor area.