Concrete for a 22×32 slab
8.69 cubic yards (431 × 80 lb bags)
for a 22×32 ft slab 4 inches thick: 234.7 cu ft. Bag counts include 10% extra; at 6 inches you need 13.04 yards.
A 22×32 foot slab covers 704 square feet. At the standard 4 inch thickness for a patio, walkway or shed floor, that is 234.7 cubic feet of concrete, or 8.69 cubic yards. At this size ready-mix is cheaper and far less work than bags: about 9.75 yards, roughly $1,609 before delivery fees, against $2,802 for 431 bags of 80 lb mix.
Concrete for a 22×32 slab by thickness
| Thickness | Cubic yards | Cubic feet | 80 lb bags | 60 lb bags | 40 lb bags |
|---|---|---|---|---|---|
| 3 in | 6.52 | 176 | 323 | 431 | 646 |
| 4 in | 8.69 | 234.7 | 431 | 574 | 861 |
| 5 in | 10.86 | 293.3 | 538 | 718 | 1076 |
| 6 in | 13.04 | 352 | 646 | 861 | 1291 |
| 8 in | 17.38 | 469.3 | 861 | 1148 | 1721 |
Bag counts include 10% extra for spillage and uneven ground. Cubic yards and cubic feet are the exact volume.
How it’s worked out
- Convert the thickness to feet: 4 in ÷ 12 = 0.333 ft.
- Multiply length × width × thickness: 32 × 22 × 0.333 = 234.67 cu ft.
- Divide by 27 for cubic yards: 234.67 ÷ 27 = 8.691 cu yd.
- Add 10% and divide by the bag yield: 258.13 ÷ 0.6 = 431 bags of 80 lb mix (rounded up).
Under the slab, plan on 4 inches of compacted gravel: about 8.69 cubic yards. For driveways and anything that carries a vehicle, go to 5 or 6 inches and add rebar or wire mesh.
Change the numbers
Other slab sizes
- 22×30 slab
- 20×32 slab
- 24×32 slab
- 22×28 slab
- 22×36 slab
- 25×32 slab
- 18×32 slab
- 26×32 slab
- 22×26 slab
- 22×25 slab
- 22×24 slab
- 22×40 slab
Questions
- How many bags of concrete do I need for a 22×32 slab?
- At 4 inches thick, a 22×32 slab takes 431 bags of 80 lb concrete mix, 574 bags of 60 lb mix or 861 bags of 40 lb mix, including 10% extra.
- How many yards of concrete for a 22×32 slab?
- 8.69 cubic yards at 4 inches thick, 10.86 at 5 inches and 13.04 at 6 inches, before adding extra for waste.
- How much does a 22×32 concrete slab cost?
- The concrete alone for a 4 inch 22×32 slab costs about $2,802 in 431 bags of 80 lb mix (at about $7 a bag) or about $1,609 for 9.75 yards of ready-mix (at about $165 a yard, before delivery fees). Professionally poured slabs usually run $6 to $12 per square foot, about $4,224 to $8,448 for 704 sq ft.
- How much does a 22×32 slab weigh?
- About 17 tons at 4 inches thick (concrete weighs about 145 lb per cubic foot).