Columbus ADU permit requirements
Last reviewed: June 22, 2026
Quick answer
Permitting an accessory dwelling unit (ADU) in Columbus, Ohio means pulling a building permit from the local authority that issues it. ArchPermit tracks 16 source-cited requirements (11 required, the rest conditional) for this jurisdiction. Submittals go through Columbus Citizen Access Portal. 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 Columbus. Every item links to its authoritative source; items that vary are flagged to confirm locally.
As of ADU code changes effective Dec 24 2025, Columbus permits ADUs by-right in all residential and apartment-residential districts, with no zoning variance for a conforming ADU (one ADU per lot generally; up to ~1,000 sf or 65% of the principal dwelling's net floor area, whichever is greater; max height 25 ft; lot coverage ≤65%; no added parking). BZS recommends a Preliminary Zoning Review to confirm conformance; a Board of Zoning Adjustment variance is required only if the project doesn't meet code. A building permit is always required. (By-right specifics come from BZS summaries + reporting; confirm against codified Title 33.)
- ADU Zoning Site Plan + Data Tablerequired
Zoning site plan with a Data Table: parcel #, lot sf, living area of primary vs ADU, ADU % of primary, heights, # units, % lot coverage, % rear-yard occupied, and required vs provided parking.
source · reviewed 2026-06-22 - Building Permit Applicationrequired
Completed BZS residential building-permit application (owner, applicant, contractor reg #, parcel, scope, sq ft, cost).
source · reviewed 2026-06-22 - Dwelling-Unit Tree Requirementrequired
The site plan must show the dwelling-unit (landscaping) tree requirement for the added unit.
source · reviewed 2026-06-22 - Electrical Planrequired
Receptacle, switch, light, fan, smoke-detector, and panel locations; service-load calculations if adding load.
source · reviewed 2026-06-22 - Energy Conservation Compliancerequired
Plans must convey the energy-code-compliance method (Prescriptive, Home Builders Association method, or REScheck).
source · reviewed 2026-06-22 - Floor Plans (every floor)required
Layout of every floor where work occurs; every room labeled; scaled or dimensioned; new vs existing differentiated.
source · reviewed 2026-06-22 - Mechanical (HVAC) Planrequired
Furnace, A/C unit, and gas-meter locations; ventilation; gas piping and prefab-fireplace details.
source · reviewed 2026-06-22 - Plot Plan / Site Planrequired
Site plan with dimensions to property lines and other structures; scaled and north-oriented.
source · reviewed 2026-06-22 - Plumbing Planrequired
New fixture locations; drain/stack/water-service/distribution sizes; pipe materials; fixture schedule; tie-in points.
source · reviewed 2026-06-22 - Scope of Workrequired
Bullet-point list of exactly what is planned, divided into Structural, Electrical, Mechanical, and Plumbing.
source · reviewed 2026-06-22 - Two (2) Complete Sets of Plansrequired
Two complete plan sets; incomplete submittals are rejected.
source · reviewed 2026-06-22 - Board of Zoning Adjustment (BZA) Variance Applicationconditionalverify locally
Required only if the ADU does not meet by-right code (e.g. setback/height/second ADU). By-right status (eff. 12/24/2025) confirmed via reporting; not yet verified against codified Title 33.
source · reviewed 2026-06-22 - Certificate of Appropriatenessconditional
Required before the permit if the property is in a historic district, commission area, East Franklinton Overlay, or University Impact District.
source · reviewed 2026-06-22 - Fire Separation Wallsconditional
Required on plans for 2 & 3 family dwellings, or for any wall less than 5 ft from a property line.
source · reviewed 2026-06-22 - Preliminary Zoning Reviewconditional
Recommended pre-step: a Zoning Review form + site plan emailed to confirm conformance / identify needed variances.
source · reviewed 2026-06-22 - Property Owner's Building Permit Affidavitconditional
Required only when the property owner (not a licensed contractor) is the permit holder.
source · reviewed 2026-06-22
Columbus ADU permit questions
- Do I need a permit to build an ADU in Columbus?
- Yes. An accessory dwelling unit (ADU) in Columbus requires a building permit. ArchPermit tracks 16 cited requirements for this jurisdiction (11 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 Columbus?
- Core required items include: ADU Zoning Site Plan + Data Table; Building Permit Application; Dwelling-Unit Tree Requirement; Electrical Plan; Energy Conservation Compliance; Floor Plans (every floor), plus 5 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 Columbus?
- Columbus accepts permit submittals via Columbus Citizen Access Portal. ArchPermit prepares a draft package you can submit there after a licensed architect reviews and seals it.