Building permits are issued by your local government, specifically the city building department if you live inside an incorporated city or town, or the county building or planning department if you live in an unincorporated area. That local agency enforces the building code, reviews your plans, and sends inspectors out to the job site. If you build without one, you can be hit with a stop-work order, daily fines, a demand to tear out finished work, denied insurance claims if something later goes wrong, and serious complications when you try to sell the house.
Which Agency Actually Issues the Permit
In the construction world, the agency with authority to issue permits and enforce the code is called the Authority Having Jurisdiction, or AHJ.1National Fire Protection Association (NFPA). A Better Understanding of NFPA 70E: What Makes Someone an Authority Having Jurisdiction For most homeowners, the AHJ is a local building department. In cities it may be called “Community Development” or “Development Services.” In unincorporated areas, the county handles it.
States generally don’t issue building permits themselves, but they set the floor. Every state has adopted some edition of the International Building Code or the International Residential Code, with the 2021 edition the most common cycle currently in use.2MiTek. International Codes Adoption by State (December 2025) Local jurisdictions can amend or add to that model code, so the rules in your city may not match the next one over. States also sometimes retain direct authority over specialized installations such as elevators and certain electrical systems, even where a local department handles everything else.
One point worth separating out: a building permit is not a zoning approval. Zoning controls what you can use the land for and how much of the lot you can build on. A building permit governs how you physically construct the project to meet structural, fire, and safety codes. Most building departments check zoning compliance when they review your application, so a conflict will usually surface early, but if you need a variance or a rezoning, that goes to a separate board on its own timeline.
When You Need a Permit and When You Don’t
The default rule in the International Residential Code is broad. If you plan to construct, enlarge, alter, repair, move, demolish, or change the occupancy of a building, you need a permit before you start. The same goes for installing or replacing electrical, gas, mechanical, or plumbing systems. That sweeps in most of what homeowners actually want to do: additions, kitchen and bathroom remodels that move plumbing or wiring, new HVAC, removing a wall, converting a garage to living space, building a deck, installing a pool.
Projects that catch people off guard include reroofing, replacing a water heater, installing a wood-burning stove or fireplace insert, and adding or relocating electrical circuits. All of those typically require a permit.
The model residential code does carve out a list of exempt work. Local jurisdictions may modify it, but the standard exemptions are a reliable baseline:
- One-story detached accessory structures such as sheds or playhouses with a floor area of 200 square feet or less
- Fences 7 feet tall or shorter
- Retaining walls 4 feet or shorter, measured from the bottom of the footing, unless they support extra weight above
- Sidewalks and driveways
- Cosmetic interior work: painting, wallpaper, tile, carpet, cabinets, countertops, and similar finish work
- Decks no larger than 200 square feet, no more than 30 inches above grade, and not attached to the house
- Prefabricated swimming pools less than 24 inches deep
- Residential playground equipment
- Window awnings projecting no more than 54 inches from an exterior wall that don’t need additional support
Minor electrical work such as swapping a light switch or outlet in kind, portable heating and cooling appliances, and small gas-appliance repairs are also typically exempt. One important qualifier: exempt from permitting does not mean exempt from code. A 150-square-foot shed still has to meet setback and construction standards. You just don’t need the paperwork to build it.
When you’re not sure, call the building department before starting. A five-minute phone call avoids the problems in the next section.
What Happens If You Build Without a Permit
Skipping the permit is one of those shortcuts that looks cheap upfront and gets expensive in every direction later. The consequences stack.
Stop-Work Order and Daily Fines
If an inspector discovers unpermitted construction, the first move is a stop-work order. All activity halts until you apply for permits retroactively, which usually costs significantly more than the original permit fee would have. Daily fines for unpermitted work can run into hundreds of dollars per day, and ignoring a stop-work order escalates to court-imposed penalties.
Forced Demolition or Reconstruction
When unpermitted work doesn’t meet code, the department can require you to tear it out and rebuild it correctly. Depending on how far along the project is, that can mean stripping finished walls to expose framing and wiring for inspection, or in the worst cases, demolishing an entire addition. The cost of doing the work twice, plus penalties, routinely doubles or triples the original project budget.
Insurance Claim Denials
Homeowner’s policies generally cover damage from covered perils like fire and storms, but insurers can deny claims when the damage traces back to unpermitted work. If an electrical fire starts in an unpermitted room addition, the insurer’s argument is simple: the wiring was never inspected, never confirmed to code, and the resulting damage is the homeowner’s problem. Even when the unpermitted work isn’t the direct cause of the loss, its presence can complicate or delay the claim.
Problems When You Sell
Unpermitted work creates a paper trail that follows the property. Sellers in most states are legally required to disclose known unpermitted work to buyers, and failing to disclose opens the door to lawsuits after closing. Buyers and their lenders routinely flag the issue in due diligence. Appraisers may not give you credit for unpermitted square footage, and some lenders will refuse to finance the purchase until the work is permitted and inspected. Expect lower offers and a smaller pool of willing buyers.
Property Tax Reassessment Anyway
Permitted work triggers a reassessment in many jurisdictions, and some homeowners skip the permit specifically to avoid the tax increase. That strategy backfires. Assessors use aerial photography, neighbor complaints, and other tools to find improvements, and when they catch unpermitted work, you pay the higher assessment anyway, often retroactively, on top of the code-enforcement penalties. The tax bump from a properly permitted project is predictable and modest compared with the combined cost of fines, forced corrections, and back taxes.
Who Pulls the Permit, and Why It Matters
Either the property owner or a licensed contractor can apply for a building permit, and the choice determines who bears the risk if something goes wrong. When you hire a licensed contractor and the contractor’s name is on the permit, the contractor takes on responsibility for code compliance and passing inspections, backed by their license and insurance.
If you pull the permit yourself as an owner-builder, you step into the contractor’s shoes. You’re personally responsible for meeting code at every inspection, managing subcontractors, and ensuring the finished work is sound. The financial exposure is real. If an unlicensed worker is injured on your property, your homeowner’s insurance may not cover it, and you could face liability for their medical costs. You may also be considered an employer under federal and state tax law, with obligations to withhold payroll taxes and carry workers’ compensation insurance for anyone you pay.
Owner-builders can and do succeed. The point is that the risk profile is different from hiring a licensed general contractor, and anyone whose name goes on the permit should understand what that signature carries.
If You’ve Already Built Without a Permit
Unpermitted work can usually be legalized after the fact through a retroactive, or “as-built,” permit process with the same local building department that would have issued the original permit. Expect to pay more than the original permit fee, and expect the inspector to require access to covered-up work: drywall opened to expose wiring, framing, and plumbing that would normally have been inspected during rough-in. If the work meets code, you get the permit and move on. If it doesn’t, you’ll be ordered to bring it into compliance before any certificate or sign-off issues. Doing this voluntarily, before an inspector finds the work on their own, generally produces a better outcome than being discovered.