Flower Mound, TX Accessory Structures: ADU Rules (2026)

Flower Mound regulates accessory dwelling units through Chapter 98 of the Code of Ordinances (Zoning). Guest quarters or accessory living spaces may be permitted in certain single-family residential zoning districts as an accessory use to the primary dwelling, subject to conditions including that the structure must be architecturally compatible with the main home and must not be independently rented or leased as a separate dwelling unit. The accessory structure must comply with all setback, height, and lot coverage requirements for the applicable zoning district. A building permit is required for construction, and the structure must meet adopted building codes including the International Residential Code. Separate utility meters are generally not permitted for accessory structures in residential zones, which effectively prevents independent rental use. Texas has no statewide ADU mandate comparable to California or Oregon, so local zoning authority controls ADU policy in Flower Mound. The Cross Timbers Conservation Development District overlay may impose additional environmental and design restrictions on accessory structures in certain areas. Homeowners should contact Planning Services at (972) 874-6350 to verify current ADU allowances for their specific zoning district and lot.