Building permits, zoning and land rules in Charleston County, South Carolina

Yes. Unincorporated Charleston County requires a building permit for most residential construction, issued by county Building Inspection Services¹. South Carolina counties must enforce the statewide building codes within their jurisdiction, and each county must place its unincorporated area under a building official^9,10. The 2021 South Carolina Building Codes have been in effect since January 1, 2023, and the 2024 code editions do not take effect for local jurisdictions until January 1, 2027^11,12. The county publishes its own building permit fee schedule, with a $75 minimum permit or inspection fee and a $250 filing fee for construction in flood zones; confirm current amounts with Building Inspection Services^13,14. The county enforces the 2021 International Residential Code with modifications, and updated mandatory codes apply to projects submitted on or after January 1, 2027¹⁵. If you plan to build your own home, South Carolina's owner-builder exemption lets a property owner act as an unlicensed builder for a qualifying one- or two-family residence, provided you personally supervise the work, sign the required disclosure and file a public notice with the register of deeds; selling or renting within two years of completion creates a presumption you didn't qualify⁶.

Charleston County Building Inspection Services, at 4045 Bridge View Dr. in North Charleston, issues building permits and runs inspections for unincorporated parts of the county; call (843) 202-6930 or email buildingservices@charlestoncounty.org¹⁴. Code enforcement has its own line at (843) 202-6994, and you can request an inspection by phone, by fax to (843) 202-6936, or through the county's online permitting portal¹⁴. The same department's Floodplain Management Division handles flood-zone and FEMA flood-map questions at floodservices@charlestoncounty.org¹⁴. Zoning determinations, rezonings and subdivision review go through the separate Zoning & Planning Department at the same address, (843) 202-7200 or planning@charlestoncounty.org².

Yes, but the correct authority depends on the parcel. Charleston County administers zoning in unincorporated areas, while municipal rules apply inside incorporated municipalities³. The county publishes its Zoning and Land Development Regulations Ordinance and zoning districts online, so identify both the jurisdiction and district before planning a house, accessory structure or other use³. Accessory-dwelling setbacks and buffers are district-specific, with additional rules in certain residential districts and on critical-line parcels³. We could not confirm one countywide numeric minimum lot size, lot-coverage limit, building-height limit or minimum dwelling size; ask Zoning & Planning for the parcel's standards². Dividing land is also regulated: a subdivision plat generally cannot be recorded, and a building permit cannot be issued for it, until it has the required approval; a parcel division of five acres or more with no new street is an information-record exception¹⁶.

The South Carolina Department of Environmental Services (SCDES), not Charleston County, permits septic systems on properties without public or community sewer, and its approval is required before the county can issue a building permit⁴. A Permit to Construct is valid for five years before renewal⁴. SCDES cannot issue an onsite wastewater permit where public or community sewer is accessible, so verify sewer availability first¹⁷. During installation, the installer must schedule an inspection before covering the system; if the inspector has not arrived within 30 minutes, a licensed installer may self-inspect and submit the approved final-inspection form⁴. Only about 1.9% of Charleston County's soils rate free of severe limits for a conventional drain field, so get a site evaluation before budgeting for a standard system⁸. A private well also needs a state permit: the owner, agent or driller must submit a Notice of Intent to SCDES before construction, with a $70 fee for an individual residential well or $50 for an irrigation well⁷.

In unincorporated Charleston County, an RV cannot be used for living, sleeping or housekeeping on residential property or outside a legally established RV park or campground³. Municipal regulations control inside incorporated municipalities, so ask the municipality about an RV stay there³. We could not confirm a separate tiny-home occupancy rule or a countywide minimum dwelling size; ask Zoning & Planning about the parcel and proposed dwelling². A tiny home intended as a dwelling still needs building-code and zoning review^3,11. Manufactured housing units on individual parcels are allowed in most agricultural and residential zoning districts, with conditions in the RR, S-3, R-4 and UR districts, and the zoning permit requires a site plan and proof of SCDES septic and well approval or public sewer and water³. Converting an accessory structure into an accessory dwelling requires a zoning permit, and only one accessory dwelling is allowed per lot³. In the Rural Area, the lot must be at least 50% larger than the minimum for a principal structure and the accessory dwelling's heated area cannot exceed 1,500 square feet³.

1. Determine whether county or municipal zoning applies, then identify the parcel's zoning district before designing³.
2. Apply to SCDES for septic, or confirm public sewer access, and apply for a private well permit if needed^4,7.
3. Obtain the county zoning permit required for driveway construction and ask Public Works about work in the county road right-of-way^3,18. For a state highway, SCDOT's standard driveway has a maximum paved throat width of 16 feet¹⁹.
4. Check flood-zone status with the Floodplain Management Division; in flood zones, flood elevation certificates are required before specified inspections^14,20.
5. Submit plans to Building Inspection Services for permit review under the 2021 South Carolina codes^11,14.
6. If you qualify as an owner-builder, sign the permit application and file the required public notice with the register of deeds⁶.
7. Schedule building inspections as construction proceeds and the septic inspection before that system is covered^4,14. Final inspection requires final SCDES septic approval or sewer approval²¹.

Check septic soils first: only 1.9% of the county's soils rate free of severe limits for a conventional drain field, so get a site evaluation before you count on a standard system⁸. Charleston County is flat lowcountry terrain, with 100% of its land at 15% slope or less, so soils and water may matter more than grading⁸. About 19.9% of the county is federal land, so verify legal access and neighboring ownership on rural tracts⁸. The county sees severe drought in about 5.3% of years and averages 50.1 inches of rain annually, making drainage and flood review practical early checks⁸. Typical annual carrying costs include a property tax bill of about $1,864 at an effective rate near 0.4% and homeowner's insurance of about $3,279⁸. Before closing, determine the zoning authority, confirm flood status and make sure the planned driveway can receive its zoning and road-access approvals^3,14,18.