Accessory Structures in Charleston, SC (2026)
9 verified accessory structures rules for Charleston, South Carolina, sourced directly from the municipal code and official government pages.
Verified from official government sources
ADU Rules
Charleston allows Accessory Dwelling Units (ADUs) in certain residential zones. ADUs must meet size, setback, and design standards. A permit is required and the property owner must reside on-site.
Charleston ADU / Accessory Dwelling Rules
Some RestrictionsADU Permits
Charleston permits accessory dwelling units (ADUs) on certain single-family lots under the Charleston Zoning Ordinance (Title 54). An ADU requires a zoning permit and a building permit issued through Charleston Permit Center, with construction subject to the 2021 International Residential Code as adopted by the South Carolina Building Codes Council. Properties within the Old & Historic District or Old City District also require Board of Architectural Review (BAR) approval before any exterior work, including new accessory dwellings.
Charleston ADU Permit Process
Some RestrictionsADU Impact Fees
Charleston does not impose broad municipal impact fees on ADUs, but new connections to Charleston Water System (CWS) trigger water and sewer tap fees and capacity charges. Any local impact fee in South Carolina must comply with the strict procedural rules of the SC Development Impact Fee Act (SC Code Title 6, Chapter 1, Article 9, §6-1-2010 et seq.), which requires a capital improvements plan, public hearings, and a rational nexus between the fee and the service. Standard zoning and building permit fees from the Charleston fee schedule apply.
Charleston ADU Impact Fees
Some RestrictionsADU Owner Occupancy
Charleston's Short-Term Rental Permit Program requires owner-occupancy of the primary residence when an ADU is used as a short-term rental, but the Zoning Ordinance does not impose a general owner-occupancy condition on long-term rental of an ADU. Owner-occupancy is enforced via the STR permit affidavit and inspections. Long-term rental of an ADU as a separate household is allowed in permitted zones without an owner-residence affidavit, subject to standard SC landlord-tenant law (SC Code Title 27, Chapter 40).
Charleston ADU Owner Occupancy
Some RestrictionsADU Rental Restrictions
Charleston allows long-term rental of an ADU but imposes one of the most restrictive short-term rental regimes in the country under the 2018 Short-Term Rental Permit Program. STRs are limited to specific zoning categories, require owner-occupancy of the primary residence, cap the rentable area at no more than 50% of the home's bedrooms, and require a city STR permit, business license, and remittance of state and local accommodations taxes. Long-term rental (30+ days) is generally permitted under standard SC landlord-tenant law.
Charleston ADU Rental Restrictions
Heavy RestrictionsShed Rules
Charleston allows sheds as accessory structures with setback and size requirements. Sheds over 200 square feet or requiring electrical/plumbing generally need a building permit.
Charleston Shed & Outbuilding Rules
Some RestrictionsGarage Conversions
Charleston allows garage conversions to living space with a building permit and compliance with zoning and building codes. Converted garages must meet residential building standards for habitable space.
Charleston Garage Conversion Rules
Some RestrictionsCarport Rules
Charleston regulates carports as accessory structures under the Zoning Ordinance. Structures over 120 sq ft require a zoning permit, plus a building permit through the Permit Center. Historic district carports require Board of Architectural Review (BAR) approval.
Carport Rules in Charleston, SC
Some RestrictionsTiny Homes
Charleston has no standalone tiny-home ordinance. Tiny dwellings on permanent foundations are regulated as accessory dwelling units under Zoning Ordinance Section 54-214, capped at 850 sq ft. SC adopts IRC Appendix Q for tiny houses 400 sq ft or less.
Tiny Home Rules in Charleston, SC
Heavy RestrictionsLooking for Charleston County county-wide rules?
County ordinances apply to unincorporated areas and may supplement Charleston city rules.
Accessory Structures in Charleston County →