Concrete for a 26×36 slab
11.56 cubic yards (572 × 80 lb bags)
for a 26×36 ft slab 4 inches thick: 312 cu ft. Bag counts include 10% extra; at 6 inches you need 17.33 yards.
A 26×36 foot slab covers 936 square feet. At the standard 4 inch thickness for a patio, walkway or shed floor, that is 312 cubic feet of concrete, or 11.56 cubic yards. At this size ready-mix is cheaper and far less work than bags: about 12.75 yards, roughly $2,104 before delivery fees, against $3,718 for 572 bags of 80 lb mix.
Concrete for a 26×36 slab by thickness
| Thickness | Cubic yards | Cubic feet | 80 lb bags | 60 lb bags | 40 lb bags |
|---|---|---|---|---|---|
| 3 in | 8.67 | 234 | 429 | 572 | 858 |
| 4 in | 11.56 | 312 | 572 | 763 | 1144 |
| 5 in | 14.44 | 390 | 715 | 954 | 1430 |
| 6 in | 17.33 | 468 | 858 | 1144 | 1716 |
| 8 in | 23.11 | 624 | 1144 | 1526 | 2288 |
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 × 26 × 0.333 = 312 cu ft.
- Divide by 27 for cubic yards: 312 ÷ 27 = 11.556 cu yd.
- Add 10% and divide by the bag yield: 343.2 ÷ 0.6 = 572 bags of 80 lb mix (rounded up).
Under the slab, plan on 4 inches of compacted gravel: about 11.56 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
- 25×36 slab
- 24×36 slab
- 28×36 slab
- 26×32 slab
- 26×40 slab
- 22×36 slab
- 30×36 slab
- 26×30 slab
- 26×28 slab
- 20×36 slab
- 32×36 slab
- 26×26 slab
Questions
- How many bags of concrete do I need for a 26×36 slab?
- At 4 inches thick, a 26×36 slab takes 572 bags of 80 lb concrete mix, 763 bags of 60 lb mix or 1144 bags of 40 lb mix, including 10% extra.
- How many yards of concrete for a 26×36 slab?
- 11.56 cubic yards at 4 inches thick, 14.44 at 5 inches and 17.33 at 6 inches, before adding extra for waste.
- How much does a 26×36 concrete slab cost?
- The concrete alone for a 4 inch 26×36 slab costs about $3,718 in 572 bags of 80 lb mix (at about $7 a bag) or about $2,104 for 12.75 yards of ready-mix (at about $165 a yard, before delivery fees). Professionally poured slabs usually run $6 to $12 per square foot, about $5,616 to $11,232 for 936 sq ft.
- How much does a 26×36 slab weigh?
- About 22.6 tons at 4 inches thick (concrete weighs about 145 lb per cubic foot).