Concrete for a 8×26 slab
2.57 cubic yards (128 × 80 lb bags)
for a 8×26 ft slab 4 inches thick: 69.3 cu ft. Bag counts include 10% extra; at 6 inches you need 3.85 yards.
A 8×26 foot slab covers 208 square feet. At the standard 4 inch thickness for a patio, walkway or shed floor, that is 69.3 cubic feet of concrete, or 2.57 cubic yards. At this size you can mix 128 bags of 80 lb (about $832 and a long day of mixing) or order 3 yards of ready-mix (about $495, plus the short-load fee most suppliers charge under 3 to 4 yards).
Concrete for a 8×26 slab by thickness
| Thickness | Cubic yards | Cubic feet | 80 lb bags | 60 lb bags | 40 lb bags |
|---|---|---|---|---|---|
| 3 in | 1.93 | 52 | 96 | 128 | 191 |
| 4 in | 2.57 | 69.3 | 128 | 170 | 255 |
| 5 in | 3.21 | 86.7 | 159 | 212 | 318 |
| 6 in | 3.85 | 104 | 191 | 255 | 382 |
| 8 in | 5.14 | 138.7 | 255 | 339 | 509 |
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: 26 × 8 × 0.333 = 69.33 cu ft.
- Divide by 27 for cubic yards: 69.33 ÷ 27 = 2.568 cu yd.
- Add 10% and divide by the bag yield: 76.27 ÷ 0.6 = 128 bags of 80 lb mix (rounded up).
Under the slab, plan on 4 inches of compacted gravel: about 2.57 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
- 8×25 slab
- 8×24 slab
- 8×28 slab
- 8×22 slab
- 8×30 slab
- 8×20 slab
- 8×32 slab
- 6×26 slab
- 10×26 slab
- 8×18 slab
- 5×26 slab
- 8×16 slab
Questions
- How many bags of concrete do I need for a 8×26 slab?
- At 4 inches thick, a 8×26 slab takes 128 bags of 80 lb concrete mix, 170 bags of 60 lb mix or 255 bags of 40 lb mix, including 10% extra.
- How many yards of concrete for a 8×26 slab?
- 2.57 cubic yards at 4 inches thick, 3.21 at 5 inches and 3.85 at 6 inches, before adding extra for waste.
- How much does a 8×26 concrete slab cost?
- The concrete alone for a 4 inch 8×26 slab costs about $832 in 128 bags of 80 lb mix (at about $7 a bag) or about $495 for 3 yards of ready-mix (at about $165 a yard, before delivery fees). Professionally poured slabs usually run $6 to $12 per square foot, about $1,248 to $2,496 for 208 sq ft.
- How much does a 8×26 slab weigh?
- About 5 tons at 4 inches thick (concrete weighs about 145 lb per cubic foot).