How much concrete do I need for a 16×20 patio?
≈ 3.95 cubic yards
That’s about 178 bags of 80-lb concrete mix (or 238 60-lb bags) for a 16×20 area at 4″ thick.
A 16 ft × 20 ft patio is 320 square feet. Poured at the standard 4-inch slab thickness, that’s 106.7 cubic feet of concrete — about 3.95 cubic yards.
| Area | 320 sq ft |
| Thickness | 4 in |
| Volume | 3.95 cu yd (106.7 cu ft) |
| 80-lb bags | 178 bags |
| 60-lb bags | 238 bags |
Tip: buy ~10% extra for spillage and uneven subgrade. For a thicker pour (driveways are often 5–6″), use the calculator to adjust.
Change the size → open the concrete calculatorGrab the supplies
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