Garland, TX Accessory Structures: ADU Rules (2026)

58, Accessory Building Regulations, governs every accessory structure in Garland, including Accessory Dwellings, and sets the rules that let a garage apartment or backyard cottage exist at all. An Accessory Dwelling must follow the same front-yard and street-side-yard setbacks as the main house, and in a non-street interior side or rear yard it needs at least a three-foot setback. No accessory building, including a dwelling, may be built without a main building already on the lot, except a barn or agricultural building in the Agricultural district, and habitation is otherwise prohibited unless it qualifies under this section.

Size is capped in two ways: total accessory floor area on a lot cannot exceed thirty percent of the main building's floor area, though that percentage cannot be used to force an accessory building smaller than six hundred square feet. Height then scales with size: an accessory building over two hundred square feet is capped at fifteen feet with a ten-and-one-half-foot maximum wall height, while one over five hundred square feet is capped at twenty-five feet, or the main structure's height if lower, with a twelve-and-one-half-foot maximum wall height.

Any accessory building or dwelling over twenty square feet needs a Building Permit under Chapter 4, Article 1, Division 4. An Accessory Dwelling cannot be sold separately from the main property and cannot be sublet on its own, and the Chapter 6 definition confirms it must not be involved in the conduct of a business.