Columbia ADU permit requirements
Last reviewed: June 22, 2026
Quick answer
Permitting an accessory dwelling unit (ADU) in Columbia, South Carolina means pulling a building permit from the local authority that issues it. ArchPermit tracks 14 source-cited requirements (9 required, the rest conditional) for this jurisdiction. Submittals go through Access Columbia (Tyler EnerGov Self-Service). These requirements were last reviewed June 22, 2026; confirm the exact forms and fees with the local permitting authority.
A source-cited checklist of what an ADU (accessory dwelling unit) permit package needs in City of Columbia. Every item links to its authoritative source; items that vary are flagged to confirm locally.
(City of Columbia, South Carolina — not Columbia, MO.) The UDO permits ADUs as 'Allowed Conditional' (C) accessory to a single-family detached dwelling across the residential districts (§ 17-4.3(d)(1)) — allowed if the standards are met (coded 'C', not by-right 'P', not special exception 'S'). The owner must occupy the principal dwelling or the ADU as a permanent full-time residence; one ADU per lot; floor area ≤ the lesser of 1,000 sf or 50% of the principal dwelling's floor area; one kitchen; one extra off-street parking space; no rentals under 30 days; must match the principal's architecture. A Design/Historic overlay (DD/DP) requires a Certificate of Design Approval before the permit. Plans are submitted as a single PDF via Access Columbia.
- Building Plans (floor + framing + foundation)required
Floor plan with room uses/fixtures/smoke detectors/egress windows; framing details (sizes/species/spans); footing & foundation plan with cross-section and crawl-space ventilation; insulation specs.
source · reviewed 2026-06-22 - Completed Checklist (applicant-initialed)required
The application's 'Checklist for All Applications', completed and submitted with the application.
source · reviewed 2026-06-22 - Construction Documents (single PDF)required
No paper — construction plans in a single PDF containing all documents (large sets may be divided by discipline).
source · reviewed 2026-06-22 - Contract / Verification of Job Costrequired
One copy establishing project valuation.
source · reviewed 2026-06-22 - Energy Efficiency Compliancerequiredverify locally
IECC mandatory provisions plus a prescriptive or performance path (REScheck acceptable). The checklist still cites 2009 IECC — confirm the current adopted SC energy code edition.
source · reviewed 2026-06-22 - Plan Review Fee ($25)required
A $25 plan-review fee due with submittal.
source · reviewed 2026-06-22 - Residential Building Permit Application (signed)required
Main application — select Use & Occupancy 'Accessory Structure' + Type of Work 'New Construction.' Captures applicant/SCLLR license, property/tax-map ref, zoning (setbacks/height/stories), valuation, and signature.
source · reviewed 2026-06-22 - Site Planrequired
Address(es), tax-map sheet #, building location with actual setbacks & distances to other buildings, parking/driveway, north arrow, scale (≥1"=20'), vicinity map, lot-coverage calc, and curb-cut location.
source · reviewed 2026-06-22 - Submittal List (index of documents)required
A list of the documents provided in the digital construction-document PDF.
source · reviewed 2026-06-22 - Address Request Formconditional
Required to obtain an address before the permit if none is assigned.
source · reviewed 2026-06-22 - Certificate of Design Approval (Design/Historic overlay)conditional
Required before permit issuance for exterior work in a DD/DP overlay district.
source · reviewed 2026-06-22 - Floodplain / Floodway Documentationconditionalverify locally
Sign the floodplain statement; if applicable, show the relationship of construction to the 100-yr floodplain (a separate flood-development permit/elevation certificate may apply).
source · reviewed 2026-06-22 - Home Builder Qualifications / Subcontractor Listconditional
Lists the license holder (SCLLR #) and subcontractors; required when a licensed builder applies.
source · reviewed 2026-06-22 - Homeowner Affidavit (owner-builder)conditional
SC owner-builder exemption certification — required only if the owner acts as the builder (own use/occupancy, deed notice).
source · reviewed 2026-06-22