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Do I Need a Building Permit? Free Permit Checker by Country
Pick your country and the work you plan. You get the official rule: no permit, a simple notice, a full building permit, or a decision left to your local authority — with the size limits, the legal reference and a link to the source.
United States · Extension (adding floor area)
Building permit needed
You need a building permit before you start.
Each city or county adopts the code with its own changes, and zoning rules (setbacks, height) apply separately.
Rules: International Residential Code (IRC) 2021, R105.2 — as adopted by each city or county
All common works — United States
United States: 3 of 9 common works need no permit, 0 need a notice, 4 need a building permit and 2 are decided locally.
| Work | Rule |
|---|---|
| Your local authority decidesfinish work (paint, tiles, cabinets, countertops) needs no permit; moving walls, wiring or plumbing usually does | |
| Building permit needed | |
| Building permit needed | |
| No permit neededup to 18.6 m²; single storey; not attached to the house | |
| No permit neededup to 18.6 m²; at most 76 cm above the ground; not attached to the house | |
| No permit neededup to 2.13 m high | |
| Building permit neededcheck the code your city or county adopted | |
| Building permit neededprefabricated pools less than 61 cm deep need no permit | |
| Your local authority decidescheck the code your city or county adopted |
Questions to ask your local authority
- Does my plot have a local or detailed plan, and what does it allow for this work?
- Do I need a permit, a notice, or nothing — and how long does it take?
- Which drawings and documents must I submit, and must an architect or engineer sign them?
- Is the house in a protected, heritage or conservation area?
- What are the distances to the boundary and the maximum heights?
Always check
- Listed or protected buildings and conservation areas usually need approval even for small works.
- In an apartment building or a gated community, the owners' association or developer may need to agree.
- Building codes still apply without a permit: structure, fire safety, electricity and drainage.
- Neighbours' rights and easements apply even when no permit is needed.
How it works
Choose your country
The rules come from that country's building law or official government guidance.
Choose the work
Interior changes, extensions, sheds, pergolas, fences, solar panels, pools or windows.
Read the conditions
See the limits and the legal reference, open the source, and save the result to your house.
Frequently asked questions
Do I need a permit for a garden shed or a pergola?
Often not, if it is small. Most countries exempt a small shed or pergola within a set area and height, away from the street and the boundary. The limits differ a lot: choose your country above to see the exact numbers and the source.
What is the difference between a permit and a notice?
A building permit is approved before you start. A notice or declaration is a simpler filing: you tell the authority what you will do, and in some countries you may start right away or after a short waiting period.
Do I need a permit to renovate inside my home?
Usually not for finishes such as paint, floors and kitchens. Removing or changing a load-bearing wall almost always needs an engineer, and in many countries a notice or a permit. In an apartment the building's owners may also need to agree.
Where do these rules come from, and are they up to date?
Each rule links to the law or the government guidance it comes from. All sources were checked on November 12, 2026. Rules change and local plans can be stricter, so confirm with your local authority before you start.
General information from official sources, not legal advice. Local plans and conditions can differ — confirm with your local authority before you build.