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

Spalding County's zoning code recognizes two related paths to a second dwelling on a residential lot. Countywide, Section 203(31) defines a mother-in-law suite simply as an accessory structure to a single-family detached dwelling, and that use appears as a permitted accessory use inside the AR-1 Agricultural and Residential district's list at Section 503(C)(17), alongside similar listings repeated for AR-2 and the other single-family districts. Because the code does not attach a floor-area limit, setback or occupancy restriction to that specific listing, a mother-in-law suite in AR-1 is regulated the same way any other accessory structure is: it must meet the district's accessory-use setbacks and the building permit process under Section 408.

The more detailed standard sits inside the Tri County Crossing (TCC) Overlay District, an area around the intersection of U.S. Highway 19/41 and Zebulon Road created to implement the county's 2009 Livable Centers Initiative plan. Section 2202B(A) defines an accessory dwelling unit there as a dwelling unit not greater than forty percent of the floor area of the primary dwelling unit, located on the same residential lot, and Section 2205B(A)(1) lists accessory dwelling units among the TCC District's permitted principal uses, meaning the ADU does not need a special exception or rezoning inside that overlay.

A property owner outside the TCC boundary who wants a garage apartment, defined countywide at Section 209(15) as a self-contained housing unit built within or on top of a garage, attached or detached, but always with a separate entrance from the main house, works from the general accessory-use rules of whichever base district applies rather than the TCC's forty-percent cap.