An accessory dwelling unit, or ADU, is a secondary dwelling located on the same lot as a primary home. In Decatur, an ADU may be attached to the main dwelling or developed as a separate accessory structure, depending on the property and applicable zoning requirements.

ADUs are one way Decatur supports “missing middle” housing — smaller-scale housing options that help fill the gap between single-family homes and larger multi-family developments. They can provide flexible space for long-term renters, family members, caregivers, aging relatives, or homeowners looking for additional housing options within an established neighborhood setting.

The City of Decatur allows one ADU per lot of record, subject to the requirements of the property’s zoning district and the standards in the City’s Unified Development Ordinance. ADUs are currently allowed in the R-50, R-60, R-85, RS-17, RM-18, RM-22, RM-43, and PO zoning districts.

Current ADU standards include several important requirements. The property owner must occupy either the primary dwelling or the ADU as their permanent residence for at least eight months of each year. An ADU may not exceed 800 square feet of floor area, may not be smaller than 300 square feet, may not exceed 40 percent of the floor area of the primary dwelling, and may have no more than two bedrooms. ADUs are also subject to applicable parking, building code, utility, lot coverage, and permitting requirements.

Because zoning, lot size, parking, historic district rules, and building code requirements can vary by property, homeowners should confirm eligibility with the City of Decatur Planning & Zoning Division before beginning design or construction.

As a housing option, ADUs continue to reflect Decatur’s goals of supporting neighborhood-scale housing, flexibility, diversity, and affordability while maintaining the character of established residential areas.

Atlanta continues to grow, and housing affordability remains one of the region’s most important challenges. As demand for housing increases, many residents are navigating higher rents, limited inventory, and greater competition for homes across a range of price points.

The City of Atlanta’s housing strategy has evolved from the earlier One Atlanta: Housing Affordability Action Plan to Mayor Andre Dickens’ current Moving Atlanta Forward housing agenda. The City’s stated goal is to create or preserve 20,000 affordable housing units by 2030, with a focus on development without displacement, preserving existing affordability, using public land for mixed-income housing, and connecting residents with practical housing support.

Affordable housing is also a top concern across the metro area. The Atlanta Regional Commission’s 2025 Metro Atlanta Speaks survey found that housing affordability ranked as the region’s leading issue, ahead of traffic, crime, and the economy.

For residents seeking help, the City of Atlanta’s Housing Help Center provides resources for renters, homebuyers, homeowners, and households facing housing-related challenges such as rental assistance, eviction prevention, legal aid, home repairs, utility assistance, and code concerns.