Atlanta’s Bonaventure-Somerset Historic District has a specific area rule for a detached single-family dwelling in an accessory building. It is a named-district provision, not Atlanta’s citywide ADU limit.
Local standards
The selected local standards are summarized in the Atlanta Zoning Ordinance §16-20U.011(6)(e), Bonaventure-Somerset Historic District. Under §16-20U.011(6)(e), the detached unit may not exceed the lesser of 1,200 square feet or 50% of the principal building’s area. The provision also excludes ADU floor area from the section’s separate calculation limiting other accessory-building area to 40% of principal-building area.
Confirm the applicable rule
These are two different comparisons: the ADU’s own lesser-of cap and the separate accessory-building calculation. Exclusion from the latter does not remove the ADU’s own maximum or other requirements. Confirm the historic district, underlying zoning, remaining code provisions, and current historic-review requirements. Consult the City’s current code text and applicable historic-review requirements before relying on this selected example. Zoning measurements do not by themselves establish fire separation, building-code compliance, utility capacity, or permit approval. For shared measurement methods, see the setback and separation guide and floor-area guide.
