Do you need a permit to lay concrete?

National answer

noneset locally, not federally

Usually exempt

like-for-like flatworkvaries by jurisdiction

Usually permitted

structural workfootings, foundations, walls

Second agency

public worksfor right-of-way work

Short version

• There is no national answer. Permitting is a local decision, jurisdiction by jurisdiction.
• Replacing a patio or walkway in the same place, size and thickness is frequently exempt.
• Footings, foundations, retaining walls, and slabs that support structures are usually permitted.
• A driveway apron in the public right of way is normally a separate approval from public works.
• Call the building department first. One phone call costs nothing; removing unpermitted work costs a lot.

Why is there no national answer to this?

Building permits in the United States are issued by local jurisdictions, not by the federal government, and that is the whole reason this question has no single answer. The International Code Council publishes model codes — the International Building Code and the International Residential Code among them — but a model code has no legal force until a state, county, or municipality adopts it.

Adoption is uneven and constantly changing. States adopt different editions in different years, and many delegate adoption to counties or cities. ICC maintains a code adoption map showing which edition each state is on. Local governments then amend what they adopted, and those amendments are where permit thresholds and exemptions frequently get rewritten.

Home rule adds another layer. In many states a city can set requirements stricter than the state’s, so two neighboring towns can treat the same patio differently.

The practical consequence is that any web page telling you a specific square footage or thickness triggers a permit is describing one jurisdiction, possibly out of date, and possibly not yours. ICC Digital Codes lets you read the code your jurisdiction actually adopted.

General information, not engineering advice. Structural work should be designed by a licensed engineer.

What concrete work is commonly exempt from a permit?

Replacement in kind is the most common exemption pattern. Many jurisdictions do not require a permit to tear out an existing patio, walkway, or slab and replace it in the same footprint, at the same elevation, with the same general construction, because nothing about the site changes.

Small, non-structural slabs on grade are the second common pattern. A pad for a shed, a grill, or an air conditioner condenser often falls below a jurisdiction’s threshold for permitted work, and many model-code-based ordinances include a list of minor work exempted from permits.

Both patterns come with conditions that are easy to miss. The exemption typically evaporates if the work changes elevation, increases area, alters drainage, encroaches on a setback or easement, or involves anything structural. Exempt from a building permit also does not mean exempt from zoning, from an HOA, or from a floodplain or wetland review.

None of this is guaranteed in your city. These are patterns, not rules, and the only way to know is to ask.

What concrete work usually requires a permit?

Four categories come up repeatedly.

Structural concrete is the clearest. Footings, foundation walls, piers, slabs that support a building, and retaining walls above a certain height are structural elements, and jurisdictions permit and inspect them because failure has consequences. Residential structural concrete requirements are addressed in ACI 332, and structural design generally is governed by ACI 318.

Work in the public right of way is the second, and it surprises homeowners. The strip between the sidewalk and the street usually belongs to the city or the state DOT, not to you, so a driveway apron, a curb cut, or sidewalk replacement typically requires a separate permit or encroachment approval from public works or the transportation department, sometimes with its own bond and inspection.

Changes to drainage or impervious coverage are the third. Adding a large slab increases runoff, and many jurisdictions cap the percentage of a lot that can be covered by impervious surfaces or require stormwater management above a threshold. Larger land-disturbing projects can also trigger federal NPDES construction stormwater permitting administered through EPA and the states.

New construction is the fourth: a new garage, an addition, or a pool deck is permitted as part of the larger project.

Who issues the permit, and what else might apply?

The building department issues building permits, but it is rarely the only office involved in a concrete project.

Public works or the state DOT handles anything in the right of way — aprons, curb cuts, sidewalk work, and street closures for a pump truck. Planning or zoning reviews setbacks, easements, lot coverage, and historic district requirements. Floodplain administrators review work in mapped flood zones, and a slab that changes grade in a flood zone is a real issue rather than a formality.

Environmental review can apply near wetlands, streams, and shorelines, and EPA’s construction stormwater program applies to projects disturbing enough land. Utility easements are their own constraint, since pouring a slab over a utility easement can mean the utility removes it later at your expense.

Homeowner associations operate outside the government entirely. An HOA can require architectural approval for a patio that the city does not care about at all, and HOA enforcement is a private contract matter.

Call the utility locate service by dialing 811 before any excavation, regardless of permits. That is separate from the permitting process and applies to essentially all digging.

What happens if you skip the permit?

Consequences vary by jurisdiction, but the pattern is consistent enough to plan around. Work discovered without a permit typically draws a stop-work order, and the jurisdiction may require the owner to apply retroactively, often at a higher fee. Where the work cannot be inspected because it is already buried, the remedy can be exposing or removing it.

Unpermitted work also follows the property. Missing permits routinely surface during a sale, when a buyer’s inspector or the title process flags work that does not match records, and the seller ends up permitting or removing it under deadline pressure.

Insurance and liability are the quieter risk. Where unpermitted structural work contributes to a loss, coverage disputes are possible, and the homeowner may carry liability that would otherwise have sat with a licensed contractor working under permit.

Contractor licensing is a separate local requirement from permitting. Many jurisdictions require concrete contractors to be licensed or registered, and hiring an unlicensed contractor can shift risk onto the homeowner regardless of whether a permit was pulled.

How do you find out what your jurisdiction requires?

Call the building department and describe the project in plain terms: what you are pouring, how big, how thick, where on the lot, and whether anything structural or any grade change is involved. Permit counters answer this question all day and the call is free.

Ask four specific things. Does this work require a building permit? Does any part of it fall in the public right of way, and if so who approves that? Are there lot coverage, drainage, or setback limits that apply? And is a licensed contractor required?

Read the adopted code yourself if you want to verify what you are told. ICC Digital Codes hosts adopted codes, and ICC’s code adoption map shows which edition your state is working from. Remember that local amendments override the model text, so the municipal code is the final word.

Get it in writing when the answer is “no permit needed.” An email from the permit desk costs nothing and settles the question years later when someone asks.

Common mistakes

• Trusting a permit threshold you read online — thresholds are local, amended, and change over time; the number that applies is your jurisdiction’s.
• Forgetting the right of way — the driveway apron and the sidewalk usually belong to the city, and that approval is separate from a building permit.
• Assuming exempt from a building permit means exempt from everything — zoning, drainage, floodplain, easements and the HOA are separate reviews.
• Pouring first and asking later — buried work that cannot be inspected sometimes has to be removed.
• Skipping the utility locate — dialing 811 before digging is separate from permitting and applies almost everywhere.