Concrete slab cost dataset

Cost by size, and what share is concrete

National figures at 4 inches with a 4-inch base, wire mesh, a broom finish, excavation and cut joints.

Two things fall out of this table. The per-foot rate improves sharply up to about 400 square feet and then flattens, because the fixed costs — getting a crew and a truck to the site — are spread further. And the concrete share rises with size for the same reason: on a small pad you are mostly buying set-up.

Inches to cubic yards

On the default 20 × 20 slab. Quantity is area × thickness ÷ 12 ÷ 27, plus 8% over — nobody orders the exact figure, because a pour that runs short is a cold joint through the middle of the slab.

Finishing hours, which is where the skill is

Those rates are our estimate. What they are trying to capture is that finishing is the one part of a slab that cannot be paused: concrete sets on its own schedule, and a stamped finish means pressing mats across the whole surface inside the window the mix allows. That is why it costs more than twice a broom finish in labour, not because the mats are expensive.

What reinforcement actually does

None

Fibre in the mix and nothing else. Acceptable on a small, well-based, low-traffic pad, and a false economy anywhere a vehicle goes.

Welded wire mesh

A sheet of mesh lifted into the middle of the pour. It does not stop cracks; it holds the two sides of a crack together, which is a different and more useful thing.

Rebar grid

Number three or four bar on a grid, tied and chaired. What a driveway or a garage floor should have, and what a thin quote leaves out first.

None of them stop concrete cracking — nothing does, because concrete shrinks as it cures. What steel does is hold the two sides of a crack together so the slab stays one piece, and what control joints do is decide where the crack goes.

Line items

The two reinforcement lines are alternatives, never both, and so are the finish materials. Breaking out an existing slab brings its own line and its own regulation.

The reasoning behind each figure

Written out so a concrete contractor can point at the exact assumption that is wrong.

Ready-mix concrete, deliveredestimated, ±22%

• Quantity is area × thickness ÷ 12 ÷ 27, plus 8% over. Nobody orders the exact figure: a pour that runs short is a cold joint through the middle of the slab, and the overage is the cheapest insurance on the job.
• A 3,000 to 4,000 psi mix, which is what a residential slab takes. The band covers the difference between a plain mix and one with fibre, an accelerator in cold weather or a plasticiser.
• ⚠️ This price assumes a full load. Below about four yards the plant adds a short-load fee that can be a large fraction of the material cost, and that is priced on our concrete delivery page rather than buried here.

Compacted gravel baseestimated, ±38%

• Crushed stone under the slab, ordered at 25% over the finished volume because it compacts. It is what stops the slab bridging over a soft spot and cracking, and it is the line most often thinned to win a bid.
• The band is wide because aggregate is heavy and its delivered price is mostly haulage: the same stone costs very different money twenty miles from a quarry and two hundred.

Formwork, stakes and releaseestimated, ±44%

• Timber round the perimeter, stakes every few feet and release agent. Priced per foot of edge, which is why a long thin slab costs more per square foot than a square one of the same area.
• The top of the band is flexible board for a curved edge, which takes both more material and more time to set.

Polythene vapour barrierestimated, ±45%

• Ten or fifteen mil sheeting lapped and taped under the slab. Necessary under anything that will be enclosed or floored later, and pointless under an open patio.
• It is one of the cheapest lines here and one of the two or three that cannot be added afterwards at any price.

Welded wire mesh and chairsestimated, ±40%

• Sheet mesh with the chairs that hold it in the middle of the pour rather than on the ground. Mesh lying on the base does nothing at all, which is a common and invisible failure.

Rebar, ties and chairsestimated, ±42%

• Number three or four bar on a grid at 16 to 18 inches, tied at the crossings and chaired off the base.
• On a driveway or a garage floor this is the line to insist on. It does not stop concrete cracking — nothing does — but it keeps the crack tight instead of letting the two halves move apart.

Colour, release and stamp matsestimated, ±45%

• Colour hardener or integral colour, powder release and the mat hire. Only on a stamped finish.
• A stamped slab also needs sealing on a cycle for the rest of its life, which is a cost of ownership this figure does not include.

Concrete pump, fixed fee and hoursestimated, ±39%

• A line pump with its operator: a call-out fee plus a minimum number of hours. It is priced as a lot because that is how it is sold.
• It looks expensive next to a wheelbarrow and it usually is not, because it replaces two or three people running concrete for hours and it removes the risk of the load going off before it is placed.

Compact excavator

• Federal reimbursement rate for the machine itself, which includes fuel, maintenance and depreciation but not the operator, who is priced separately.
• One hour per 200 square feet plus an hour of set-up, on the assumption of a straightforward dig to base level rather than a site that has to be cut into a slope.

Equipment operator

• The same hours as the machine above. The FEMA rate covers the excavator; the person driving it is priced here at the wage published for your metropolitan area.
• BLS publishes this occupation in 529 of the 530 areas in our index, so this line is almost always priced by its own trade rather than by a fallback.

Haul away the spoilestimated, ±46%

• Trucking and the tip fee for the soil that comes out, at 25% swell over the dug volume because excavated ground does not go back in the hole it came from.
• Entirely local. A gate fee is a weighbridge tariff rather than anybody’s time, so the regional wage index does not touch this line and the band has to carry the whole country.

Labourer: break out and remove the old slab

• One hour per 45 square feet plus two hours of set-up, with a breaker. Old concrete comes up in pieces that have to be carried, and that is most of the time rather than the breaking.
• ⚠️ Breaking and cutting concrete is respirable crystalline silica work, covered by OSHA 29 CFR 1926.1153. In practice that means water-fed or vacuum-shrouded tools and a written exposure control plan on the job, and it is a real reason this line is not the cheap part of the job.
• The wage is official BLS data adjusted to your area; the hours are our estimate.

Haul away and tip the broken concreteestimated, ±46%

• Broken concrete is dense and it is charged by weight. Many areas will take clean concrete for recycling at a lower rate than mixed waste, which is inside the band rather than modelled separately.

Labourer: grade, compact, set forms and place steel

• Three hours of set-up plus one hour per 30 square feet. This is the largest single block of time on the job and it happens before a mixer is even ordered.
• It is also the answer to why two quotes for the same slab differ so much. Everything here is invisible the day after the pour, and the slab that lasts is the one where it was done properly.
• The wage is official BLS data adjusted to your area; the hours are our estimate.

Cement mason: place, screed, float and finish

• Two hours of set-up plus per-square-foot rates that depend entirely on the finish: 0.022 hours for a broom finish, 0.03 for a smooth trowel, 0.038 for exposed aggregate and 0.055 for stamped. A wheelbarrow run adds 40% because the concrete has to be moved as well as placed.
• This is the part of a slab that cannot be rushed and cannot be paused. Concrete sets on its own schedule, and a finisher who runs out of time gets one surface for the next thirty years.
• BLS publishes cement masons in 457 of the 530 areas in our index, so in the rest this hour falls back to the broader construction group for that same area. The hours are our estimate.

Cement mason: cut the control joints

• One hour per 250 square feet plus an hour of set-up. Joints are cut within a day of the pour, roughly a quarter of the slab depth, so the slab cracks where you decided rather than where it wants to.
• Saw-cutting cured concrete is silica work under OSHA 29 CFR 1926.1153, which is why the saw runs wet.
• A slab with no control joints will still crack. The only question is whether the crack is a straight line you chose.

Curing compound and protectionestimated, ±54%

• Spray-on curing compound, or sheeting and blankets in cold weather. Concrete gains its strength by staying wet, not by drying, which is the opposite of what most people assume.
• The cheapest line on the page and the one that decides how hard the surface ends up. A slab left to dry in the sun on day one is a slab that dusts for the rest of its life.

Not included in this dataset

What the concrete alone costs delivered

This page prices a finished slab. If what you want is the material at the kerb — a yard of ready-mix, the short-load fee under about four yards, the delivery and the waiting time — that is a different question and it has its own page. The two are deliberately not the same number.

Permits and inspections

A patio rarely needs one; a slab that will carry a structure usually does, and in many places it has to be inspected before the pour rather than after. Fees vary by jurisdiction with no national source and are excluded rather than averaged.

Footings and foundations

A slab that carries a wall needs a thickened edge or a separate footing below the frost line, and how deep that is depends on where you live. That is foundation work, it is designed rather than estimated, and it is not in these figures.

Drainage and where the water goes

A slab is an impervious surface, and adding one changes where rain ends up. Some jurisdictions limit how much of a lot can be covered. See the EPA on managing rainwater on your own ground. Grading the surroundings is not priced here.

Ground that is not ordinary

Expansive clay, fill, a high water table or tree roots through the pour area all change the base design, and sometimes require an engineer. This models a straightforward dig into stable ground.

Sealing on a cycle

Stamped and coloured concrete needs resealing every few years to keep looking like the photograph. That is a cost of ownership rather than of installation.

On breaking concrete in particular: OSHA 1926.1153, Respirable crystalline silica sets a permissible exposure limit for respirable crystalline silica and requires a written exposure control plan and a competent person on site. Retrieved 2026-08-22.