Can I add an accessory dwelling unit in McKinney?

McKinney allows accessory dwelling units, also called backyard cottages, subject to citywide standards in UDC Sec. 205G (Accessory Uses, Buildings, and Structures), item b, Accessory Dwelling Unit. Only one ADU is allowed per conforming lot, and none are permitted on small-lot single-family detached or attached lots. The ADU cannot exceed 50 percent of the primary dwelling's square footage (75 percent if the primary home is 1,200 square feet or less), must match the primary home's height and setbacks, must sit behind its front face, must share ownership with the primary home with no separate electric meter, and cannot be rented or leased separately from the primary home. Per Table 2-26's use table, an ADU is permitted as an accessory use in the R43, R12, R8, R6, R5, R3, TR1.8, and AP districts; it is not permitted in MR, MF36, MHR, or any commercial, office, industrial, or GC district. Start by confirming the zoning district through the city's zoning GIS layer or the Planning Department at 972-547-2000. This pack covers incorporated McKinney only; the ETJ and unincorporated Collin County have no municipal zoning.