Barrow County, GA Accessory Structures: ADU Rules (2026)

Barrow County Code § 89-220 defines a guest house as a detached dwelling unit used primarily for sleeping by relatives, domestic employees or temporary guests of the family occupying the principal home, and it must be an accessory use to a dwelling already on the lot rather than a standalone residence. The county limits a lot to no more than one guest house, and the structure must sit to the rear of the main house and stay architecturally compatible with it. Size is capped at 50 percent of the existing living area of the principal residence or 1,500 square feet, whichever figure is larger, and its placement cannot push the lot over the maximum lot coverage allowed in that zoning district.

Before a guest house can be built, the water supply and sanitary sewage disposal system serving the lot must be certified adequate to support both the main house and the guest house together, and the guest house needs its own adequate parking, accessed through the principal dwelling's existing driveway rather than a separate curb cut. Section 89-221 offers a lighter-weight alternative for households that only need extra living space for relatives rather than a full detached unit: a second cooking facility inside the single-family residence, sized no larger than the main kitchen, provided the property owner lives in the home, interior access connects the two living areas, and the household adds paved off-street parking for the additional vehicles the arrangement brings.

Neither section functions as a general accessory dwelling unit ordinance; both are narrowly limited to housing relatives, employees or guests of the existing household rather than an independently rentable unit, and short-term rental use of either structure is separately governed by the county's short-term rental ordinance referenced at section 89-222.