How Much Concrete for a 10×10 Slab?
Quick Answer
For a 10×10 foot slab at standard 4-inch thickness, you need 1.23 cubic yards of concrete — approximately 56 bags of 80-lb mix or 74 bags of 60-lb mix.
- 4 inches thick: 1.23 cubic yards = 56 bags (80 lb) or 74 bags (60 lb)
- 5 inches thick: 1.54 cubic yards = 70 bags (80 lb) or 93 bags (60 lb)
- 6 inches thick: 1.85 cubic yards = 83 bags (80 lb) or 111 bags (60 lb)
- Always order 5–10% extra for waste and spillage
Formula
Multiply length and width in feet by thickness in inches, divide by 12 to convert inches to feet, then divide by 27 to convert cubic feet to cubic yards.
Step-by-Step Calculation
- 1
Convert thickness to feet
4 inches ÷ 12 = 0.333 feet
- 2
Calculate cubic feet
10 × 10 × 0.333 = 33.3 cubic feet
- 3
Convert to cubic yards
33.3 ÷ 27 = 1.23 cubic yards
- 4
Calculate 80-lb bags
33.3 ÷ 0.6 = 55.5 → round up to 56 bags
10×10 Slab — Concrete by Thickness
| Thickness | Cubic Yards | 80-lb Bags | 60-lb Bags | Est. Cost* |
|---|---|---|---|---|
| 3 inches | 0.93 | 42 | 56 | $180–$210 |
| 4 inches | 1.23 | 56 | 74 | $240–$280 |
| 5 inches | 1.54 | 70 | 93 | $300–$350 |
| 6 inches | 1.85 | 83 | 111 | $360–$420 |
*Cost estimates based on $4.50–$5.00 per 80-lb bag at major retailers
Frequently Asked Questions
Should I use 4-inch or 6-inch thickness for a 10×10 patio?
Use 4 inches for pedestrian-only patios and walkways. Use 6 inches if the slab will support vehicles, heavy equipment, or sits on poor soil. Most residential patios are 4 inches.
Do I need rebar for a 10×10 slab?
For a 4-inch patio slab, wire mesh (6×6 W1.4×W1.4) is usually sufficient. Use #4 rebar on 18-inch centers for 6-inch slabs or if local code requires it.
How long until I can walk on my 10×10 slab?
Wait 24–48 hours before walking on it. Wait 7 days before placing heavy items. Full cure strength is reached at 28 days.