Plano, TX Building Setbacks & Zoning: Lot Coverage Limits (2026)

Zoning Ordinance § 13.700 states the governing rule: "The maximum percentage of any lot which may hereafter be covered by the main building and all accessory buildings shall not exceed the lot coverage requirements herein specified, except where an existing building at the effective date of this ordinance may have a greater percentage of a lot covered than herein prescribed, such building shall be considered a conforming use." That means every district table in Articles 9 and 10 sets its own cap, and older buildings that already exceeded today's number when the ordinance took effect are grandfathered as conforming rather than forced to comply retroactively.

The numbers vary widely by district. In the SF-7 district (§ 9.600), the "Maximum Coverage" line reads "45% total for principal and accessory buildings (See Sec. 13.500.4A)," climbing to 47.5% under Stormwater Incentive Option 1 or 50% under Option 2. SF-9 and SF-6 carry the same 45%/47.5%/50% structure. The Estate Development (ED) district is tighter, "20%, plus 10% additional coverage permitted for accessory buildings", while the Urban Residential (UR) district allows "60%, including accessory uses and/or buildings," the 2F Two-Family district reaches 65-72% depending on the stormwater option, and the UMU Urban Mixed-Use district permits single-family attached lots up to "100% including accessory buildings," with nonresidential UMU coverage limited only by front, side, and rear setback and height standards rather than a flat percentage. Section 13.500.4A is the cross-referenced provision governing how the 10% accessory-building credit is calculated against the base coverage figure.