Birmingham, AL Accessory Structures: ADU Owner Occupancy (2026)

Alabama is a Dillon Rule state and has not enacted ADU legislation overriding local zoning. The Birmingham Zoning Ordinance defines accessory uses and permits accessory living quarters in lower-density Residence districts (R-1, R-2, R-3, R-4) as a use incidental to the principal single-family dwelling. The practical effect is that the principal dwelling must remain occupied as a single-family residence and the accessory unit must be used by family members, household guests, or domestic employees — converting both units to separate non-related rentals generally triggers a two-family-dwelling classification that requires R-5, R-6, or R-7 zoning or a use variance from the Board of Zoning Adjustment. Property owners seeking to rent both the main dwelling and the ADU to unrelated tenants typically pursue a Board of Zoning Adjustment use variance or a zoning map amendment through the Birmingham Planning Commission. There is no recorded deed-restriction requirement comparable to California Junior ADU rules. The Department of Planning, Engineering and Permits verifies use through the Certificate of Occupancy issued under Code Title 1 Chapter 6 and through complaint-driven code enforcement.