1 county-level rule, plus city-specific rules for 2 cities in Charleston County, South Carolina.
Verified from official government sources
Charleston County allows one accessory dwelling unit (ADU) per existing lot under Section 6.5.9 of the Zoning and Land Development Regulations (ZLDR). In the Rural Area, the lot must be at least 50% larger than the district minimum and the ADU's heated gross floor area cannot exceed 1,500 square feet; in the Urban/Suburban Residential and RO districts, ADUs follow the dimensional setback standards of Section 6.5.8.B.3 but are not required to sit wholly behind the principal structure. Detached ADUs require a separate electrical meter; attached ADUs may not have one.
2 cities in Charleston County have their own accessory structures rules. Each link goes to that city's dedicated page with code citations.
See every category we cover for Charleston County — parking, noise, fences, fires, animals, pools, and more.
Charleston County Ordinance Hub →