Concrete for a 26×28 slab
8.99 cubic yards (445 × 80 lb bags)
for a 26×28 ft slab 4 inches thick: 242.7 cu ft. Bag counts include 10% extra; at 6 inches you need 13.48 yards.
A 26×28 foot slab covers 728 square feet. At the standard 4 inch thickness for a patio, walkway or shed floor, that is 242.7 cubic feet of concrete, or 8.99 cubic yards. At this size ready-mix is cheaper and far less work than bags: about 10 yards, roughly $1,650 before delivery fees, against $2,893 for 445 bags of 80 lb mix.
Concrete for a 26×28 slab by thickness
| Thickness | Cubic yards | Cubic feet | 80 lb bags | 60 lb bags | 40 lb bags |
|---|---|---|---|---|---|
| 3 in | 6.74 | 182 | 334 | 445 | 668 |
| 4 in | 8.99 | 242.7 | 445 | 594 | 890 |
| 5 in | 11.23 | 303.3 | 557 | 742 | 1113 |
| 6 in | 13.48 | 364 | 668 | 890 | 1335 |
| 8 in | 17.98 | 485.3 | 890 | 1187 | 1780 |
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: 28 × 26 × 0.333 = 242.67 cu ft.
- Divide by 27 for cubic yards: 242.67 ÷ 27 = 8.988 cu yd.
- Add 10% and divide by the bag yield: 266.93 ÷ 0.6 = 445 bags of 80 lb mix (rounded up).
Under the slab, plan on 4 inches of compacted gravel: about 8.99 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
- 25×28 slab
- 26×26 slab
- 26×30 slab
- 24×28 slab
- 28×28 slab
- 25×26 slab
- 24×26 slab
- 26×32 slab
- 22×28 slab
- 28×30 slab
- 22×26 slab
- 20×28 slab
Questions
- How many bags of concrete do I need for a 26×28 slab?
- At 4 inches thick, a 26×28 slab takes 445 bags of 80 lb concrete mix, 594 bags of 60 lb mix or 890 bags of 40 lb mix, including 10% extra.
- How many yards of concrete for a 26×28 slab?
- 8.99 cubic yards at 4 inches thick, 11.23 at 5 inches and 13.48 at 6 inches, before adding extra for waste.
- How much does a 26×28 concrete slab cost?
- The concrete alone for a 4 inch 26×28 slab costs about $2,893 in 445 bags of 80 lb mix (at about $7 a bag) or about $1,650 for 10 yards of ready-mix (at about $165 a yard, before delivery fees). Professionally poured slabs usually run $6 to $12 per square foot, about $4,368 to $8,736 for 728 sq ft.
- How much does a 26×28 slab weigh?
- About 17.6 tons at 4 inches thick (concrete weighs about 145 lb per cubic foot).