City · Ohio
ADU rules in Columbus
These are the primary sources for accessory dwelling unit regulations in Columbus: the city's own zoning code, planning department pages, and permit guides. Start here before talking to anyone: the rules below are what your permit reviewer will apply.
Rules at a glance
An ADU may be in a detached building. Detached ADUs must be in the rear yard, meet district side yards (or match a legally established detached garage's side yards if above or within it), and may occupy up to 45 percent of the rear yard (55 percent for two detached ADUs).
C.C. 3332.355.B.1, 3332.355.CAn ADU may be attached or internal to the principal dwelling (or apartment house in apartment districts), with permanent living, sleeping, eating, cooking, and sanitation facilities and its own separate entrance.
C.C. 3332.355.B.1; C.C. 3333.325.B.1Height capped at the principal dwelling's height or 25 feet; internal conversions of legally existing buildings may keep the existing building's height if taller. Lot coverage on a lot with an ADU may not exceed 65 percent.
C.C. 3332.355.B.3, B.5No owner-occupancy condition appears anywhere in the ADU sections or elsewhere in the Ord. 2526-2025 code changes; the general provisions impose number, size, height, and location requirements only.
C.C. 3332.355 (section contains no owner-occupancy requirement)ADUs are expressly exempt from additional parking, and also from area district lot-width and frontage requirements.
C.C. 3332.355.B.8; C.C. 3333.325.B.8Allowed by right in all residential (Ch. 3332) and apartment residential (Ch. 3333) districts since Ord. 2526-2025 (adopted Nov 24, 2025, effective late Dec 2025); previously ADUs required a City Council variance. Building permits are still required, and Certificates of Appropriateness or Approval apply in historic and architectural review areas.
C.C. 3332.355; Ord. 2526-2025 preambleNo minimum lease term is stated in the ADU sections. Chapter 598 requires short-term rental permits citywide.
C.C. 3332.355.A; C.C. 3333.325.AThe fine print: 5 caveats that can change the picture
- By-right ADUs are new: Ord. 2526-2025 was adopted Nov 24, 2025 and took effect in late December 2025; before that every ADU needed a Council variance (110 variances approved 2019-2025).
- Allowed number varies by district: one ADU on a single-unit lot in most residential districts; in R-2F, one ADU on a single- or two-unit lot; in R-4, two ADUs on lots with up to four units (max five dwelling units per lot); apartment residential lots (Ch. 3333) with a single principal building may add two ADUs; larger multiple-dwelling developments may add ADUs up to a 5 percent unit increase.
- Detached ADUs are restricted to the rear yard and to 45 percent of rear-yard area (55 percent for two), and total lot coverage is capped at 65 percent.
- Certificates of Appropriateness or Approval are required for ADUs in historic districts and architectural review areas, on top of building permits.
- The ADU rules live in legacy Title 33 (Chapters 3332/3333), not in the Zone In 2024 zoning code (Title 34); properties rezoned into the 2024 code follow Title 34's own rules, and ADUs on lots governed by a limited overlay follow Chapter 3370 except for unit-count and unit-size limits.
Summarized from Columbus's ordinance text, read July 2026; every row links the code section it came from. Rules often vary by zone and lot, so treat this as orientation, not a permit determination, and confirm with the planning department before you commit to a design.
ADU regulations
- library.municode.comOfficial sourceVerified July 2026Code of Ordinances §3332.355https://library.municode.com/oh/columbus/codes/code_of_ordinances?nodeId=TIT33ZOCO_CH3332REDI_3332.355ACDWUNAD
- library.municode.comOfficial sourceVerified July 2026Code of Ordinances §3333.325https://library.municode.com/oh/columbus/codes/code_of_ordinances?nodeId=TIT33ZOCO_CH3333APDI_3333.325ACDWUNAD
- columbus.legistar.comOfficial sourceVerified July 2026https://columbus.legistar.com/LegislationDetail.aspx?ID=7743645&GUID=D87D9CFE-225B-4A5C-9015-3482794E8FFB&FullText=1
- columbus.govOfficial sourceReviewed July 2026https://www.columbus.gov/files/sharedassets/city/v/1/building-and-zoning/accessory-dwelling-units-adu.pdf
Short-term rental rules
Planning to rent your ADU on Airbnb or VRBO? Columbus regulates short-term rentals separately; check these before counting on nightly rental income.
Spotted something outdated?
Zoning codes change. If a link is dead or Columbus has updated its ordinance, report it and we'll verify against the official source.
Report a correctionReady to build?
Planning an ADU in Columbus?
Tell us about your project and we'll match you with vetted local designers and builders as we bring them online. No cost, no obligation.