Vestavia Hills, AL Accessory Structures: ADU Rules (2026)

1. The math matters: if the Accessory Dwelling is built above or beside parking that also serves the main house, that shared parking area is excluded from the 25 percent calculation; if parking is added specifically for the Accessory Dwelling, that square footage counts toward the cap. Location is restricted too. 2, the unit must be placed to the side or rear of the principal dwelling, never in front of it, and must observe the same side and rear setback distances required of the principal structure, so a homeowner cannot push an Accessory Dwelling closer to a property line than the main house is allowed to sit.

3: the Accessory Dwelling cannot open onto a separate street from the one the principal dwelling already uses, which keeps garage apartments and backyard cottages from creating a second curb cut or driveway. 4 imposes a design-matching rule whenever the unit can be seen from the public right-of-way: its exterior colors, materials and roof pitch must be consistent with the principal home. 8 cannot issue until the completed unit conforms to these standards.