Where you can build a shed without a permit
We analyzed the building code in every U.S. state to find out where a backyard shed needs a permit — and where it doesn't.
The short answer
In much of the United States, you can legally build a backyard shed up to 200 square feet without pulling a building permit.
That number isn't arbitrary. It comes from Section R105.2 of the International Residential Code (IRC), the model code that nearly every state builds its residential rules on. R105.2 exempts "one-story detached accessory structures" — the technical term for a shed — as long as the floor area stays at or under 200 square feet. (Before the 2009 edition of the IRC, the limit was only 120 square feet; it was raised because most prefabricated sheds on the market landed between the two.)
But "the United States" is really 50 separate rulebooks. Some states apply that 200-square-foot rule statewide. Others hand the decision entirely to your city or county. And one state doesn't use the residential code at all. Here's how it breaks down.
What we found
The map
New York City uses its own building code separate from New York State. Tiles are positioned approximately; see the table below for each state's details.
State-by-state breakdown
The table shows the edition of the IRC each state currently references, whether the rule is set at the state or local level, and what that means for a shed permit. Where a state defers to local jurisdictions, your city or county sets the threshold — commonly between 100 and 200 square feet.
| State | IRC edition | Code authority | Shed building permit |
|---|---|---|---|
| Alabama | 2021 | Statewide | Not required under 200 sq ft † |
| Alaska | 2018 | Local (Anchorage statewide) | Set by local jurisdiction |
| Arizona | 2018 | Local | Set by local jurisdiction |
| Arkansas | 2021 | Local (state buildings only) | Set by local jurisdiction |
| California | 2024 | Statewide (CA Codes) | Not required under 200 sq ft † |
| Colorado | 2021 | Local (home rule) | Set by local jurisdiction |
| Connecticut | 2021 | Statewide | Not required under 200 sq ft † |
| Delaware | 2018 | Local | Set by local jurisdiction |
| District of Columbia | 2015 | District-wide | Not required under 200 sq ft † |
| Florida | 2021 | Statewide | Not required under 200 sq ft † |
| Georgia | 2024 | Statewide | Not required under 200 sq ft † |
| Hawaii | 2018 | Local (by county) | Set by local jurisdiction |
| Idaho | 2024 | Statewide | Not required under 200 sq ft † |
| Illinois | Local | Local | Set by local jurisdiction |
| Indiana | 2018 | Statewide | Not required under 200 sq ft † |
| Iowa | 2024 | Statewide | Not required under 200 sq ft † |
| Kansas | 2018 | Local | Set by local jurisdiction |
| Kentucky | 2015 | Statewide | Not required under 200 sq ft † |
| Louisiana | 2021 | Statewide | Not required under 200 sq ft † |
| Maine | 2021 | Cities over 4,000 | Varies (large towns only) |
| Maryland | 2021 | Statewide + local | Not required under 200 sq ft † |
| Massachusetts | 2021 | Statewide + local | Not required under 200 sq ft † |
| Michigan | 2015 | Statewide | Not required under 200 sq ft † |
| Minnesota | 2018 | Statewide | Not required under 200 sq ft † |
| Mississippi | 2012–2018 | Local | Set by local jurisdiction |
| Missouri | 2018 | Local | Set by local jurisdiction |
| Montana | 2021 | Local option | Set by local jurisdiction |
| Nebraska | 2018 | Local (residential) | Set by local jurisdiction |
| Nevada | 2024 | Statewide + local | Not required under 200 sq ft † |
| New Hampshire | 2021 | Statewide | Not required under 200 sq ft † |
| New Jersey | 2021 | Statewide | Not required under 200 sq ft † |
| New Mexico | 2021 | Statewide | Not required under 200 sq ft † |
| New York | 2024 | Statewide (exc. NYC) | Not required under 200 sq ft † |
| North Carolina | 2015 | Statewide | Not required under 200 sq ft † |
| North Dakota | 2021 | Statewide | Not required under 200 sq ft † |
| Ohio | 2018 | Statewide | Not required under 200 sq ft † |
| Oklahoma | 2018 | Statewide | Not required under 200 sq ft † |
| Oregon | 2021 | Statewide | Not required under 200 sq ft † |
| Pennsylvania | 2021 | Statewide (opt-in) | Not required under 200 sq ft † |
| Rhode Island | 2021 | Statewide | Not required under 200 sq ft † |
| South Carolina | 2021 | Statewide | Not required under 200 sq ft † |
| South Dakota | 2021 | Local option | Set by local jurisdiction |
| Tennessee | 2021 | Statewide | Not required under 200 sq ft † |
| Texas | 2021 | Statewide (local may exceed) | Not required under 200 sq ft † |
| Utah | 2024 | Statewide | Not required under 200 sq ft † |
| Vermont | 2021 | Uses IBC, not IRC | Different framework — verify locally |
| Virginia | 2021 | Statewide | Not required under 200 sq ft † |
| Washington | 2021 | Statewide | Not required under 200 sq ft † |
| West Virginia | 2018 | Statewide | Not required under 200 sq ft † |
| Wisconsin | 2015 | Statewide (WI UDC) | Not required under 200 sq ft † |
| Wyoming | 2024 | Local | Set by local jurisdiction |
† The exemption applies only to a detached, one-story shed used for storage. It does not waive zoning rules, and several conditions can require a permit anyway — see below.
The catch: a permit-free shed still has rules
Even where no building permit is required, "no permit" does not mean "no rules." Homeowners are caught off guard by these every year:
What can still require a permit — or trip you up
- Electrical or plumbing. The moment you run power or water to the shed, a permit is almost always required, regardless of size.
- Zoning & setbacks. Distance from property lines, easements, and lot-coverage limits apply to every structure, permit or not.
- A stricter local limit. Many cities lower the threshold to 120 or even 100 square feet, below the national 200.
- Foundation type. A permanent slab foundation can change the classification of the structure.
- HOA approval. A separate process entirely from your city — and one the building code says nothing about.
How we did this & sources
This analysis is based on the building-permit exemption in Section R105.2(1) of the International Residential Code (IRC), which exempts one-story detached accessory structures (sheds) of 200 square feet or less from a building permit. State-by-state code editions and adoption levels come from the International Code Council's "International Codes — Adoption by State" data.
States are classified as statewide when a state-level residential code based on the IRC applies, local when there is no mandatory statewide residential code and the decision rests with the city or county, and IBC for Vermont, which regulates one- and two-family homes under the commercial building code rather than the IRC. Code adoption is dynamic and local jurisdictions frequently amend the baseline; this study is general guidance, not legal advice. Always confirm with your local building department before you build.
Primary sources: International Code Council (iccsafe.org); IRC §R105.2.
Use this data
Free to cite & republish
Journalists and writers are welcome to use these findings, the table, and the map, with a link back to the source. Suggested attribution:
Source: StateDataIndex — "Where You Can Build a Shed Without a Permit (2026)" — https://statedataindex.com/studies/shed-permit-by-state