Concrete for a 22×30 slab
8.15 cubic yards (404 × 80 lb bags)
for a 22×30 ft slab 4 inches thick: 220 cu ft. Bag counts include 10% extra; at 6 inches you need 12.22 yards.
A 22×30 foot slab covers 660 square feet. At the standard 4 inch thickness for a patio, walkway or shed floor, that is 220 cubic feet of concrete, or 8.15 cubic yards. At this size ready-mix is cheaper and far less work than bags: about 9 yards, roughly $1,485 before delivery fees, against $2,626 for 404 bags of 80 lb mix.
Concrete for a 22×30 slab by thickness
| Thickness | Cubic yards | Cubic feet | 80 lb bags | 60 lb bags | 40 lb bags |
|---|---|---|---|---|---|
| 3 in | 6.11 | 165 | 303 | 404 | 605 |
| 4 in | 8.15 | 220 | 404 | 538 | 807 |
| 5 in | 10.19 | 275 | 505 | 673 | 1009 |
| 6 in | 12.22 | 330 | 605 | 807 | 1210 |
| 8 in | 16.3 | 440 | 807 | 1076 | 1614 |
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: 30 × 22 × 0.333 = 220 cu ft.
- Divide by 27 for cubic yards: 220 ÷ 27 = 8.148 cu yd.
- Add 10% and divide by the bag yield: 242 ÷ 0.6 = 404 bags of 80 lb mix (rounded up).
Under the slab, plan on 4 inches of compacted gravel: about 8.15 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
- 22×28 slab
- 22×32 slab
- 20×30 slab
- 24×30 slab
- 22×26 slab
- 25×30 slab
- 22×25 slab
- 18×30 slab
- 26×30 slab
- 22×24 slab
- 22×36 slab
- 22×22 slab
Questions
- How many bags of concrete do I need for a 22×30 slab?
- At 4 inches thick, a 22×30 slab takes 404 bags of 80 lb concrete mix, 538 bags of 60 lb mix or 807 bags of 40 lb mix, including 10% extra.
- How many yards of concrete for a 22×30 slab?
- 8.15 cubic yards at 4 inches thick, 10.19 at 5 inches and 12.22 at 6 inches, before adding extra for waste.
- How much does a 22×30 concrete slab cost?
- The concrete alone for a 4 inch 22×30 slab costs about $2,626 in 404 bags of 80 lb mix (at about $7 a bag) or about $1,485 for 9 yards of ready-mix (at about $165 a yard, before delivery fees). Professionally poured slabs usually run $6 to $12 per square foot, about $3,960 to $7,920 for 660 sq ft.
- How much does a 22×30 slab weigh?
- About 16 tons at 4 inches thick (concrete weighs about 145 lb per cubic foot).