Concrete for a 22×36 slab
9.78 cubic yards (484 × 80 lb bags)
for a 22×36 ft slab 4 inches thick: 264 cu ft. Bag counts include 10% extra; at 6 inches you need 14.67 yards.
A 22×36 foot slab covers 792 square feet. At the standard 4 inch thickness for a patio, walkway or shed floor, that is 264 cubic feet of concrete, or 9.78 cubic yards. At this size ready-mix is cheaper and far less work than bags: about 11 yards, roughly $1,815 before delivery fees, against $3,146 for 484 bags of 80 lb mix.
Concrete for a 22×36 slab by thickness
| Thickness | Cubic yards | Cubic feet | 80 lb bags | 60 lb bags | 40 lb bags |
|---|---|---|---|---|---|
| 3 in | 7.33 | 198 | 363 | 484 | 726 |
| 4 in | 9.78 | 264 | 484 | 646 | 968 |
| 5 in | 12.22 | 330 | 605 | 807 | 1210 |
| 6 in | 14.67 | 396 | 726 | 968 | 1452 |
| 8 in | 19.56 | 528 | 968 | 1291 | 1936 |
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: 36 × 22 × 0.333 = 264 cu ft.
- Divide by 27 for cubic yards: 264 ÷ 27 = 9.778 cu yd.
- Add 10% and divide by the bag yield: 290.4 ÷ 0.6 = 484 bags of 80 lb mix (rounded up).
Under the slab, plan on 4 inches of compacted gravel: about 9.78 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
- 20×36 slab
- 24×36 slab
- 22×32 slab
- 22×40 slab
- 25×36 slab
- 22×30 slab
- 18×36 slab
- 26×36 slab
- 22×28 slab
- 16×36 slab
- 28×36 slab
- 22×26 slab
Questions
- How many bags of concrete do I need for a 22×36 slab?
- At 4 inches thick, a 22×36 slab takes 484 bags of 80 lb concrete mix, 646 bags of 60 lb mix or 968 bags of 40 lb mix, including 10% extra.
- How many yards of concrete for a 22×36 slab?
- 9.78 cubic yards at 4 inches thick, 12.22 at 5 inches and 14.67 at 6 inches, before adding extra for waste.
- How much does a 22×36 concrete slab cost?
- The concrete alone for a 4 inch 22×36 slab costs about $3,146 in 484 bags of 80 lb mix (at about $7 a bag) or about $1,815 for 11 yards of ready-mix (at about $165 a yard, before delivery fees). Professionally poured slabs usually run $6 to $12 per square foot, about $4,752 to $9,504 for 792 sq ft.
- How much does a 22×36 slab weigh?
- About 19.1 tons at 4 inches thick (concrete weighs about 145 lb per cubic foot).