Accessory Structures in Columbia, SC (2026)
4 verified accessory structures rules for Columbia, South Carolina, sourced directly from the municipal code and official government pages.
Verified from official government sources
ADU Rules
Columbia allows one accessory dwelling unit (ADU) per single-family lot under Sec. 17-4.3(d)(1). The unit can be attached to the house or built as a detached structure like a garage apartment, but it is capped at the lesser of 1,000 square feet or 50 percent of the principal dwelling's floor area, limited to one kitchen, and does not count toward maximum density.
Columbia Accessory Dwelling Unit Zoning Rules
Some RestrictionsColumbia, SC Unified Development Ordinance § 17-4.3(d)(1)
Accessory Dwelling Unit An accessory dwelling unit is allowed only as accessory to, and on the same lot as, a single-family detached dwelling unit, subject to the following standards: a. There shall be no more than one accessory dwelling unit on a lot. c. An accessory dwelling unit may be within or attached to the principal structure (e.g., a downstairs or upstairs apartment), or exist within o...
ADU Owner Occupancy
Columbia requires an owner-occupancy commitment before an accessory dwelling unit can operate. Sec. 17-4.3(d)(1)b requires that either the principal house or the ADU itself be the permanent, full-time residence of the lot's owner, so an investor cannot buy a single-family property, build an ADU, and rent out both units to non-owner tenants.
Columbia ADU Owner-Occupancy Requirement
Significant RestrictionsColumbia, SC Unified Development Ordinance § 17-4.3(d)(1)b
An accessory dwelling unit is allowed only as accessory to, and on the same lot as, a single-family detached dwelling unit, subject to the following standards: a. There shall be no more than one accessory dwelling unit on a lot. b. Either the principal dwelling unit or the accessory dwelling unit must be the permanent, full-time residence of the owner of the lot.
ADU Rental Restrictions
Columbia bans short-term rental of accessory dwelling units. Sec. 17-4.3(d)(1)i prohibits leasing or renting an ADU for any tenancy under 30 days, closing off Airbnb- or VRBO-style nightly rentals of a garage apartment or in-law suite even though the same code separately allows short-term rentals of a principal dwelling under its own Visitor Accommodation Uses standard.
Columbia ADU Short-Term Rental Ban
Significant RestrictionsColumbia, SC Unified Development Ordinance § 17-4.3(d)(1)i
g. Only one kitchen is allowed per accessory dwelling unit. h. At least one off-street parking space shall be provided in addition to those required for the primary dwelling. i. An accessory dwelling unit shall not be leased or rented for tenancies of less than 30 days.
Shed & Carport Rules
Any accessory structure in Columbia, including a storage shed, must sit at least three feet from a side or rear property line, at least five feet from the main house unless it is open on all sides, and never inside the required front yard. Sec. 17-4.3(c) also requires the shed to serve, and stay subordinate to, the principal dwelling.
Accessory Building and Shed Setbacks in Columbia
Some RestrictionsColumbia, SC Unified Development Ordinance § 17-4.3(c)
All accessory uses and accessory structures shall: Directly serve the principal use or structure; Be customarily accessory and clearly incidental and subordinate to the principal use and structure; Be subordinate in area, extent, and purpose to the principal use or structure; Be owned or operated by the same person as the principal use or structure; Be located on the same lot as the principal u...
Looking for Richland County county-wide rules?
County ordinances apply to unincorporated areas and may supplement Columbia city rules.
Accessory Structures in Richland County →