Texas City, TX Accessory Structures: ADU Rules (2026)

Texas City Code of Ordinances § 160.006 defines a guest quarter as a secondary structure on a lot that can contain dwelling accommodations for occupancy by guests, not for rent or lease or permanent occupancy, and adds that the building shall not have a separate utility meter. That definition is what a garage apartment or backyard suite runs into in Texas City, Galveston County.

The use is allowed only where a district lists it. Section 160.024(C)(2) lists guest quarters as an accessory use in District A (single-family residential) when located at least 60 feet from the front property line and meeting all other yard requirements. Section 160.025(C)(2) does the same for District A-1 with the 60 foot line and all other requirements. The accessory use lists for District A-2 (patio homes) and District B (duplex) do not include guest quarters.

Section 160.083(A) then shuts off rental income. In any district zoned for residential uses, an accessory building may not be used for commercial purposes and may not be rented. The residential districts under § 160.083(D) are A, A-1, A-2, B, C, C-1 and MH.

Placement rules from § 160.083 apply as well. An accessory building not exceeding one story can occupy not more than 60% of a minimum required rear yard, and one exceeding one story not more than 40%. It sits on the rear one-half of the lot, at least ten feet from any dwelling building on the same lot or any adjacent lot, at least five feet from any rear lot line, and under the same side yard requirements as the principal structure. In District A an accessory structure is capped at 2 stories or 25 feet, or one story or 15 feet if built with fabricated metal siding or roofing. Under § 160.111 the Building Official reviews a plan showing the location and dimensions of all accessory buildings before issuing a permit.