Permits are the least fun part of any project — and the part homeowners most often want to skip. But a permit is cheap, and the downside of building without one (fines, teardowns, a blocked home sale) is not. Here's the plain-English version of when you actually need one.
One caveat up front: rules are set locally, by your city or county building department and sometimes your HOA. The thresholds below are the common ones across the U.S., but the only authoritative answer is a two-minute call to your local building office. Treat this as what to expect, not legal advice.
Fences
A permit is commonly required when:
- The fence is taller than 6 feet (many areas cap front-yard fences at 3–4 feet and back-yard at 6–7 feet).
- It sits on or near a property line — a survey may be required to avoid encroachment disputes.
- It's near a street corner or driveway where it could block sight lines.
- You're in an HOA, which may require approval and specific materials even when the city doesn't.
A short backyard privacy fence is often the most permit-friendly project on this page. Price yours with the fence cost calculator before you plan the permit trip.
Decks
Decks trigger permits more often than fences because they're structural. Expect to need one when the deck is:
- Attached to the house — the ledger board connection is a common failure point inspectors check.
- Raised more than about 30 inches off the ground (the threshold where guardrails and footings matter).
- Larger than a set size, often around 200 square feet.
Low, freestanding "floating" decks are more likely to be exempt. If a permit is required, the inspection focuses on footings, the ledger, and railing height. Estimate the build in the deck cost calculator — and remember permit fees are separate.
Sheds
Sheds usually hinge on size. Many jurisdictions exempt small sheds under roughly 100–200 square feet, but require a permit above that, or whenever the shed has electrical or plumbing run to it. Placement rules (setbacks from property lines) apply even to permit-exempt sheds.
What a permit costs — and why it's worth it
Most residential permits run $50–$500. In exchange you get an inspection that catches unsafe footings, bad connections, and code violations before they become expensive. The alternative — building without one — risks fines, a stop-work order, or being forced to tear down and rebuild. It also comes back to bite you at resale: unpermitted structures show up in inspections and can delay or sink a sale, and they can complicate insurance claims. A few hundred dollars and a short wait is cheap insurance.
The bottom line
Before any fence, deck, or shed, make one call to your local building department with your planned height and size. Then price the project itself with the fence or deck calculator, and budget the permit as a separate line. It's the boring step that keeps a good project from becoming an expensive mistake.