McKinney, TX Accessory Structures: ADU Owner Occupancy (2026)

McKinney's Zoning Ordinance defines single-family residential districts (RS-60, RS-72, RS-84, RS-120, RED districts) as permitting one dwelling unit per lot. An accessory structure such as a guest house, pool house, or servant's quarters may be occupied by family members, household staff, or short-term guests but cannot be operated as a separate independent rental household — this is treated as an unauthorized second dwelling unit and a zoning violation enforced by Code Services. Where a Specific Use Permit (SUP) is granted to allow a true second unit, the SUP conditions typically include owner-occupancy of either the principal dwelling or the accessory unit, plus a recorded deed restriction filed with the Collin County Clerk binding the property to those conditions. Evidence of owner occupancy includes Texas driver's license at the property address, voter registration, and the Texas homestead exemption under Texas Tax Code §11.13. Texas has not preempted local owner-occupancy rules, unlike California's AB 976 — McKinney retains full home-rule authority. LLC or trust-owned properties face additional scrutiny because corporate entities cannot personally occupy a property; SUP conditions typically require the principal member or trustee residing on-site to satisfy the residency test. Within the Historic Preservation Overlay, the Historic Preservation Advisory Board may impose additional residency-related conditions on any accessory unit Certificate of Appropriateness.