Baytown, TX Accessory Structures: ADU Rules (2026)

Baytown regulates accessory structures including potential ADUs through its zoning ordinance and building codes. Accessory buildings in residential zones must be located in the rear yard and meet side and rear setback requirements, generally at least 5 feet from property lines. The accessory structure must be subordinate in size to the principal dwelling and is typically limited to a maximum of 50% of the rear yard area or a percentage of the main structure's footprint, whichever is less. Accessory buildings used as habitable living space must meet all International Residential Code requirements for residential occupancy including minimum ceiling heights, natural light, ventilation, egress windows, electrical service, plumbing connections, and smoke detectors. A building permit is required for any accessory structure, with additional plumbing and electrical permits needed if the unit includes a kitchen or bathroom. The height of accessory structures generally cannot exceed the height of the principal structure. Baytown does not have a specific ADU ordinance that streamlines the process for adding secondary dwelling units, unlike some larger Texas cities. Converting a detached garage or workshop into living space requires full building permit review. Short-term rental use of an ADU would be subject to any applicable city regulations on short-term rentals. Texas state law does not mandate that cities allow ADUs, leaving the decision to local zoning authority.