Columbus's Accessory Structures: The Rules That Matter
Every city handles accessory structures a little differently. In Columbus, Ohio, there are 3 distinct rules that residents and property owners should be aware of. Some are stricter than what neighboring cities enforce, and others are more relaxed. Here is what you need to know.
ADU Rental Restrictions
Columbus allows one accessory dwelling unit per residential lot, but renting it out short-term pulls the ADU into Chapter 598's hotel/motel and short-term-rental permit system, and the zoning code flags that ADUs may later be added to a rental registry.
Key details: ADUs per lot: 1 (2 in R-4, up to 5 total units). Max ADU size: 65% of home or 1,000 sq ft. STR permit trigger: Rentals under 30 consecutive days. Unpermitted STR fine: Up to $250 per listing. Future rule flagged: Possible citywide ADU rental registry.
Advertising or operating an unpermitted short-term-rental ADU under C.C. 598.02(A)(2) is an unclassified misdemeanor with up to a $250 fine per listing, escalating to a third-degree misdemeanor on repeat offenses, plus forfeiture of the rental's gross revenue.
This is not one of those rules that cities tend to ignore. Columbus actively enforces its adu rental restrictions requirements.
Shed & Carport Rules
Columbus caps residential sheds at 15 feet tall, ties total shed area to your zoning district's lot coverage limit, and requires a zoning clearance once combined shed area tops 200 square feet.
Key details: Max shed height: 15 feet. Zoning clearance trigger: over 200 sq ft cumulative. Side-yard shed height cap: 6 feet. Applies to: 1-, 2-, 3-unit dwellings. Lot requirement: principal building must exist.
Building without zoning clearance for sheds over 200 square feet, or exceeding the 15-foot height cap or required setbacks, brings a stop-work order and forced relocation or removal by Columbus zoning enforcement.
ADU Rules
Columbus allows one accessory dwelling unit per residential lot under Zoning Code § 3332.355, letting homeowners add a small attached, internal, or detached second unit without extra parking or a variance.
Key details: ADUs allowed: One per lot, most residential districts. Size cap: 65% of home or 1,000 sq ft. Height cap: Height of home or 25 feet. Parking: No extra off-street parking required. Penalty: First-degree misdemeanor, § 3305.99.
Building an oversized, over-height, or unpermitted ADU without zoning clearance is a first-degree misdemeanor under § 3305.99; the Building and Zoning Services director can also void the certificate and order work stopped, with each day a separate offense.
The Bottom Line
Columbus's accessory structures rules are a mixed bag. Some areas are strict, others are relaxed, and the details matter. The best approach is to check the specific rule that applies to your situation rather than assuming Columbus is broadly strict or permissive.
All of the above reflects Columbus's municipal code as of our last review. If you need specifics on fines, exemptions, or filing requirements, the detailed ordinance pages linked above have the full breakdown.