Bags or a truck?
This size can be done with bags and a rented mixer in an afternoon. Have a helper, because once you start you should place and finish the whole slab in one go.
Concrete slab charts · 8 × 8 ft
How much concrete for a 8×8 slab?
A 8 × 8 ft slab 4 inches thick needs 0.79 cubic yards of concrete (21.3 cubic feet), or about 36 bags of 80 lb premix. Add 5–10% for waste. Other thicknesses are in the table, or adjust the calculator below.
Units
8 × 8 ft slab by thickness
Exact volumes without waste. Bag counts are rounded up.
| Thickness | Cubic yards | Cubic feet | 80 lb bags | 60 lb bags | Metric |
|---|---|---|---|---|---|
| 3 in | 0.59 yd³ | 16.0 ft³ | 27 | 36 | 0.45 m³ |
| 4 in | 0.79 yd³ | 21.3 ft³ | 36 | 48 | 0.60 m³ |
| 5 in | 0.99 yd³ | 26.7 ft³ | 45 | 60 | 0.76 m³ |
| 6 in | 1.19 yd³ | 32.0 ft³ | 54 | 72 | 0.91 m³ |