How Much Does a Concrete Slab Cost in Louisiana?

Most national cost guides put a plain 4-inch concrete slab at about $4 to $8 per square foot, installed. The middle of that range is about $6. At those rates, a 30 by 40 shop slab runs about $4,800 to $9,600 before extras.

Small pads cost more per foot, and house slabs are priced on their own. These are market numbers from published guides, not our price list. We pour concrete slabs and pads across Acadiana, and every job gets a written quote.

What does a concrete slab cost by size?

A pad is just a small slab. Guide rows multiply the $4 to $8 range by common sizes. Calculator rows come from a national cost calculator set to a Lafayette ZIP code in September 2026.

The calculator prices a basic 4-inch slab with a broom finish, up to 500 square feet. Its numbers leave out dirt work and a gravel base. Setup is part of every job, and a small pad spreads it over fewer feet. Set to Lafayette, the calculator comes in about 8 percent under its own national average.

If a carport slab meets the drive, we can put the concrete driveway on the same written quote.

What drives the price of a slab?

Thickness. A 6-inch slab takes half again as much concrete as a 4-inch slab. National guides price that step at about $1 more per square foot. Floors that carry trucks or heavy equipment often go to 6 inches or more.

The ground. The pad is built up with compacted fill and a gravel base. One national guide prices a gravel base at about $1 a square foot.

The steel. Two national guides add about 35 cents a square foot for wire mesh. A rebar grid costs more, and one guide lists it at $2 to $3 a square foot. Thickened edges under the walls add about $1 to $2 a square foot.

The vapor barrier. Plastic sheeting under the slab adds about 50 cents a square foot in one guide. It slows ground moisture from rising into a floor you plan to close in.

Labor and ready-mix. One national guide puts labor at about $2 to $3 a square foot. Two guides list the concrete itself at about $110 to $126 a cubic yard. One cubic yard covers 81 square feet at 4 inches thick.

Access. When the ready-mix truck cannot reach the forms, the concrete gets pumped or wheeled in. That adds cost.

Permits and flood rules. In Lafayette, the Lafayette Consolidated Government (LCG) requires a permit for a carport or a shed. Its fee is $3.50 per $1,000 of the work’s value, with a $35 minimum. In the floodplain, LCG’s zero net fill rule means every load of fill brought in needs one taken out.

Why do Acadiana’s soils change the price?

NRCS soil surveys put most of Lafayette on silt loams. Frost silt loam, a common one, is wet within 1.5 feet of the surface most winters and springs. Around Crowley, Crowley silt loam holds water near the top in those months too. Near Breaux Bridge and Bayou Teche, clays like Sharkey and Iberia rate very high for shrink-swell.

On wet ground, the pad is often built up with compacted fill so the slab sits above the yard. Water that stands around a slab is a yard drainage question. Pour days follow the weather, too.

What does a house slab foundation cost?

National foundation guides put a house slab at about $4 to $7 per square foot. Some run as high as $14. For a 2,000 square foot footprint, $4 to $7 works out to $8,000 to $14,000.

A monolithic slab pours the footing and the slab as one piece. Other houses sit on a stem-wall slab, as the plan calls for. Under LCG’s floodplain rules, a new house’s lowest floor sits 1 foot above the base flood elevation. Slab foundations and footings are poured to the builder’s or engineer’s plan, and that plan drives the price.

What does Louisiana’s building code say about house slabs?

Houses in Louisiana are built under the Louisiana State Uniform Construction Code. In 2026 it enforces the 2021 International Residential Code, with state amendments. The state plans to move to the 2024 edition on January 1, 2027. For a slab under a house, the state building code sets these rules.

• A concrete floor on the ground is at least 3.5 inches thick (Section R506.1).
• Compacted fill tops out at 24 inches of clean sand or gravel, or 8 inches of dirt, without approval (R506.2.1).
• A vapor retarder at least 6 mil thick goes under the slab, with seams lapped 6 inches (R506.2.3).
• Louisiana’s amendment adds a Class A rating for that plastic.
• Carports and unheated accessory buildings such as garages are exempt from it.
• Exterior footings are at least 12 inches wide and 6 inches thick (R403.1.1).
• They sit at least 12 inches below undisturbed ground (R403.1.4).
• The ground falls at least 6 inches in the first 10 feet away from the house (R401.3).

Your city or parish permit office answers the rest.

Does a gravel pad or piers cost less than a slab?

For a shed, a gravel pad usually costs less. One national guide lists gravel pads at $1.25 to $1.80 per square foot. It lists a concrete slab on grade at $4 to $8, and concrete piers at $6 to $12. On a 10 by 12 shed, gravel comes to about $150 to $220, and a slab to $480 to $960.

The same guide calls gravel fine for small and medium sheds, and a slab better for heavy equipment. LCG waives the permit for a detached shed of 200 square feet or less, but only on piers or skids. For a house, one national foundation guide puts pier and beam at $5 to $10 per square foot. It puts a slab at $4 to $7.

What should a written slab quote show?

Ask for a quote that lists each part:

• The size and the thickness.
• The dirt work and the gravel base.
• Rebar or wire mesh, plus any thickened edges.
• The vapor barrier, where the plan calls for one.
• Control joints and a broom finish.
• Cleanup after the pour.

We look at the job, or you send photos, and we put the quote in writing. For a shop slab or a shed pad, see our slab and pad work and call or text (337) 520-8615.