San Angelo, TX Accessory Structures: ADU Rules (2026)

Zoning Ordinance Sec. 401 permits exactly one detached accessory apartment with full sleeping, living, kitchen and bath facilities on a lot with an existing single-family home, but only in the RS-2 (Two-Family Residential) or RM-1 (Low-Rise Multifamily) Districts, and none of its seven conditions may be varied except where the section itself allows. The apartment must stay under 900 square feet and under 50 percent of the primary structure's enclosed floor area, and either the apartment or the primary dwelling must be owner-occupied. The primary home must be at least five years old before an owner can apply for an accessory apartment permit.

Converting a detached garage into an accessory apartment is expressly allowed as long as it still meets every applicable development standard and building code, but new exterior stairs must go on the rear of the residence, or the side if the rear is infeasible, and the design should avoid new entrances or facade changes visible from the street. The apartment must meet the same minimum building setbacks and density limits that apply to accessory buildings generally under Sec. 402, and it cannot get its own utility meter: the accessory unit and the primary residence share utilities.

One additional off-street parking space is required for the accessory apartment, on the same lot as the primary dwelling, though tandem parking is allowed and the Zoning Board of Adjustment can vary that parking requirement.