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, so 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
Columbia ADU permit questions
- Do I need a permit to build an ADU in Columbia?
- Yes. An accessory dwelling unit (ADU) in Columbia requires a building permit. ArchPermit tracks 14 cited requirements for this jurisdiction (9 required, the rest conditional). Always confirm the exact forms, fees, and code edition with the local permitting authority that issues the permit.
- What does an ADU permit package require in Columbia?
- Core required items include: Building Plans (floor + framing + foundation); Completed Checklist (applicant-initialed); Construction Documents (single PDF); Contract / Verification of Job Cost; Energy Efficiency Compliance; Plan Review Fee ($25), plus 3 more. Each requirement links to its authoritative source, and nothing is permit-ready until an independent licensed professional reviews and seals it.
- How are ADU permits submitted in Columbia?
- Columbia accepts permit submittals via Access Columbia (Tyler EnerGov Self-Service). ArchPermit prepares a draft package you can submit there after a licensed architect reviews and seals it.