Accessory Structures in Mobile, AL (2026)
3 verified accessory structures rules for Mobile, Alabama, sourced directly from the municipal code and official government pages.
Verified from official government sources
ADU Rules
In Mobile's Historic Avenue Overlay, one accessory dwelling unit is allowed by right per single-family lot, capped at 50 percent of the main house's floor area and no taller than the principal dwelling.
Mobile Historic Avenue Overlay ADU Size Limits
Some RestrictionsMobile City Code § 64-15-1(D)(3)(c)-(e)
(c)Where allowed.(1)ADUs are permitted by right in the overlay on residential lots that do not have more than one (1) dwelling unit. ADUs are not permitted on lots containing a duplex, triplex or a cottage court.(d)Dimensional standards.(1)ADUs shall not exceed a gross floor area of more than 50% of the principal structure's floor area.(2)No ADU may be taller than the principal dwelling unit.(e...
Shed & Carport Rules
Mobile's UDC sets no separate size or height limit for sheds; accessory structures must stay out of required yards like any building, except for narrow encroachments listed in Table 64-3-5.1, such as an alley-loaded detached garage.
Mobile Accessory Structure Yard Rules
Some RestrictionsMobile City Code § 64-3-5.B
Except as provided below, yards shall be unoccupied and unobstructed from three (3) feet above the general ground level of the building site upward. ... Garages, attached or detached and loaded from an alley | Rear | No restriction | —
Tiny Homes
Mobile's residential building code amendments formally adopt IRC Appendix AQ, the tiny house standards, giving tiny homes a recognized construction path under the city's code.
Mobile Adopts Tiny House Building Code
Light RestrictionsMobile City Code § 28-52 (R102.5.1)
R102.5.1 Adopted Appendices. The following appendices shall be adopted: Appendix AE - Manufactured Housing Used as Dwellings Appendix AF - Radon Control Methods Appendix AH - Patio Covers Appendix AJ - Existing Buildings and Structures Appendix AK - Sound Transmission Appendix AM - Home Day Care R-3 Occupancy Appendix AO - Automatic Vehicular Gates Appendix AQ - Tiny Houses
Looking for Mobile County county-wide rules?
County ordinances apply to unincorporated areas and may supplement Mobile city rules.
Accessory Structures in Mobile County →