12×40 Concrete Driveway Thickness and Cost
A 12 by 40 ft driveway apron priced at 5 in, with 4 in and 6 in beside it.
Formula SSC-2026.1
Formula SSC-2026.1 · 4,000 PSI
Order volume
8.15 yd³
6.230 m³ placed+waste
Order weight
33,000 lb
14,969 kg
80 lb bags
367
9 pallets at 42 bags
60 lb bags
489
0.45 ft³ yield each
Rebar
684.00 ft
45 × 20 ft · 54 × 6 m · 503 lb
Ready-mix vs bags
$1,344.44
Truck $1,344.44 · 80 lb bags $2,477.25
Grid lines are equalized so the drawing stays readable. The order count uses on-center spacing with a bar at each end of the layout, then holds concrete cover in the field.
| Item | Net | Waste | Order | Unit price | Line total |
|---|---|---|---|---|---|
| Ready-mix concrete | 7.41 yd³ | 10% | 8.15 yd³ / 6.230 m³ | USD | $1,344.44 |
| Short-load fee | Full load | — | 1 truck @ 10 yd³ | USD | $0.00 |
| 80 lb pre-mix bags | 333.3 bags | 10% | 367 bags | USD | $2,477.25 |
| 60 lb pre-mix bags | 444.4 bags | 10% | 489 bags | USD | $2,640.60 |
| #4 rebar sticks, 20 ft | 45 sticks | 10% | 50 sticks / 54 × 6 m | USD | $700.00 |
| Rebar chairs | 243 crossings | 10% | 268 chairs | USD | $75.04 |
| Tie wire rolls | 243 ties | 10% | 1 rolls | USD | $8.00 |
Ready-mix truck
$1,344.44
0.81 nominal 10 yd³ loads · 1 to order
80 lb bags
$2,477.25
60 lb alternative $2,640.60 · delivery weight 33,000 lb
| Thickness | Order yd³ | Order m³ | 80 lb bags | Rebar ft | Ready-mix | 80 lb cost |
|---|---|---|---|---|---|---|
| 4 in | 6.52 | 4.984 | 294 | 752 | $1,075.56 | $1,984.50 |
| 5 in | 8.15 | 6.230 | 367 | 752 | $1,344.44 | $2,477.25 |
| 6 in | 9.78 | 7.476 | 440 | 752 | $1,613.33 | $2,970.00 |
Show the deterministic formula
Slab ft³ = L × W × thickness ÷ 12. Thickened-edge extra = footing band × (footing depth − slab thickness), with corner squares counted once.
yd³ = ft³ ÷ 27. m³ = ft³ × 0.0283168. Weight uses 150 lb/ft³, then the header converts that pound total at 1 lb = 0.45359237 kg. 80 lb bags yield 0.6 ft³ and 60 lb bags yield 0.45 ft³. Currency changes the price labels only.
Bars across a span = floor(span ÷ spacing) + 1. Order sticks = that count, plus 10, 5, or 15 percent waste, cut from 20 ft and 6 m stock. Chairs = one per grid intersection.
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Project: 12×40 Concrete Driveway Thickness and Cost
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This sheet is an estimate for ordering and layout discussion. It is not a sealed design. Confirm the quantities with a licensed local professional and the authority having jurisdiction before you buy or build.
Engineering notes
Twelve by forty feet is 480 square feet. At 5 in that is about 7.41 cubic yards before waste and about 8.15 yards at 10 percent. The comparison table repeats 4, 5, and 6 in so the extra yard of thickness is visible before you call the plant. A driveway often sees wheel loads at the edges. The default mat is #4 at 18 in. Control joints, base rock, and slope are outside this volume takeoff.
Code reference
IRC R506.1 sets a 3.5 in minimum for concrete slab-on-ground floors. Reinforcement cover and spacing follow ACI 318 practice and the local inspector. This quantity takeoff is not a soils or structural design.
Field questions
- How many yards is a 12x40 driveway at 5 inches?
- Placed volume is 200 cubic feet, or 7.41 cubic yards. A 10 percent waste factor brings the order to about 8.15 cubic yards.
- Is 4 inches cheaper by a full truck?
- Move the thickness control and read the truck-load line. On this footprint, one inch of thickness is 40 cubic feet, about 1.48 yards before waste.
- Should I add a thickened edge on a driveway?
- Leave it off for a uniform driveway slab. Turn it on only where the plan shows a thickened apron or a curb edge, then set the width and depth.