Chapel Hill, NC Building Setbacks & Zoning: Lot Coverage Limits (2026)

Section 3.8.2(j) of the Land Use Management Ordinance defines the 'Maximum Impervious Surface Ratio' shown in Table 3.8-1 as the share of a lot's gross land area that may be covered by buildings, driveways, patios, and other impervious surfaces. The section sets that ratio at .50, or 50 percent, for single-family and two-family residential development, and at .70, or 70 percent, for multifamily developments, fraternities and sororities, non-residential uses, and mixed-use development. Table 3.8-1 prints this as '.5/.7' for districts such as R-1, R-2, CC, and OI-1, where the lower figure governs one- and two-family homes and the higher figure applies once a lot carries multifamily or commercial development.

The restriction has one carve-out: section 3.8.2(j)(3) states it does not apply within the town's Town Center zoning districts, where dense, largely paved development is expected. The ratio interacts with the town's separate stormwater management standards in section 3.11.4.3, which require any development needing a form district permit to control the volume and rate of runoff leaving the site, so a homeowner who exceeds the .50 ratio on an R-1 lot faces both a zoning violation and a stormwater compliance problem.