How Much Concrete Do I Need for a 20x20 Patio?
The Short Answer
A 20x20-foot patio at 4 inches thick requires approximately 4.94 cubic yards of concrete. Order about 5.5 yards to account for waste and spillage.
The Detailed Breakdown
Volume calculated as length x width x thickness converted from cubic feet to cubic yards (divide by 27).
| Calculation | Value | Assumptions |
|---|---|---|
| Concrete Needed | 4.94 cubic yards | 20 x 20 ft x 4 inches thick |
| With 10% Waste | 5.4 cubic yards | 10% added for spillage and uneven ground |
| Estimated Cost | $750-$850 | Ready-mix concrete at $140-$160 per cubic yard |
Key Assumptions
- Standard patio thickness of 4 inches.
- Formula: length x width x thickness / 27 for cubic yards.
- Ready-mix concrete pricing at 2026 national averages.
Adjust for Your Situation
Order 5.5 cubic yards of concrete for your 20x20 patio to ensure full coverage with waste allowance.
Use the Free CalculatorWhat Affects This Result
Thickness
Increasing from 4 to 6 inches adds 50% more concrete and cost.
Ground Preparation
Uneven ground requires more concrete to achieve uniform thickness.
Reinforcement
Rebar or wire mesh adds $0.50-$1.50 per square foot but prevents cracking.