Concrete for a 26×30 slab
9.63 cubic yards (477 × 80 lb bags)
for a 26×30 ft slab 4 inches thick: 260 cu ft. Bag counts include 10% extra; at 6 inches you need 14.44 yards.
A 26×30 foot slab covers 780 square feet. At the standard 4 inch thickness for a patio, walkway or shed floor, that is 260 cubic feet of concrete, or 9.63 cubic yards. At this size ready-mix is cheaper and far less work than bags: about 10.75 yards, roughly $1,774 before delivery fees, against $3,101 for 477 bags of 80 lb mix.
Concrete for a 26×30 slab by thickness
| Thickness | Cubic yards | Cubic feet | 80 lb bags | 60 lb bags | 40 lb bags |
|---|---|---|---|---|---|
| 3 in | 7.22 | 195 | 358 | 477 | 715 |
| 4 in | 9.63 | 260 | 477 | 636 | 954 |
| 5 in | 12.04 | 325 | 596 | 795 | 1192 |
| 6 in | 14.44 | 390 | 715 | 954 | 1430 |
| 8 in | 19.26 | 520 | 954 | 1272 | 1907 |
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 × 26 × 0.333 = 260 cu ft.
- Divide by 27 for cubic yards: 260 ÷ 27 = 9.63 cu yd.
- Add 10% and divide by the bag yield: 286 ÷ 0.6 = 477 bags of 80 lb mix (rounded up).
Under the slab, plan on 4 inches of compacted gravel: about 9.63 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
- 25×30 slab
- 26×28 slab
- 26×32 slab
- 24×30 slab
- 28×30 slab
- 26×26 slab
- 22×30 slab
- 30×30 slab
- 25×26 slab
- 24×26 slab
- 26×36 slab
- 20×30 slab
Questions
- How many bags of concrete do I need for a 26×30 slab?
- At 4 inches thick, a 26×30 slab takes 477 bags of 80 lb concrete mix, 636 bags of 60 lb mix or 954 bags of 40 lb mix, including 10% extra.
- How many yards of concrete for a 26×30 slab?
- 9.63 cubic yards at 4 inches thick, 12.04 at 5 inches and 14.44 at 6 inches, before adding extra for waste.
- How much does a 26×30 concrete slab cost?
- The concrete alone for a 4 inch 26×30 slab costs about $3,101 in 477 bags of 80 lb mix (at about $7 a bag) or about $1,774 for 10.75 yards of ready-mix (at about $165 a yard, before delivery fees). Professionally poured slabs usually run $6 to $12 per square foot, about $4,680 to $9,360 for 780 sq ft.
- How much does a 26×30 slab weigh?
- About 18.9 tons at 4 inches thick (concrete weighs about 145 lb per cubic foot).