Asphalt calculator
A driveway 50 ft long and 12 ft wide, paved 2 in thick, takes 7.33 tons of hot mix asphalt, or 7.70 tons with 5% extra.
How asphalt is estimated
Hot mix asphalt is sold by the ton, and pavers estimate it by area and compacted thickness. The rule used by highway agencies is about 110 lb of mix per square yard for each inch of compacted thickness. Caltrans's maintenance tables use 111 lb, and MoDOT's figure of about 145 lb per cubic foot for compacted asphalt works out to 109 lb. The calculator uses 110.
Tons = square yards × thickness in inches × 110 ÷ 2,000
Area: 50 ft × 12 ft = 600 sq ft
70 sq yd (with 5% extra) × 2 in × 110 lb ÷ 2,000 = 7.70 tons
Enter the compacted thickness, which is what the finished pavement measures. Mix is spread thicker and rolled down, so the loose layer behind the paver is deeper than the number you enter.
Tons of asphalt by thickness
| Compacted thickness | Per 100 sq ft | Per 1,000 sq ft | 12 × 50 ft driveway |
|---|---|---|---|
| 1 in | 0.61 | 6.11 | 3.67 |
| 1.5 in | 0.92 | 9.17 | 5.50 |
| 2 in | 1.22 | 12.22 | 7.33 |
| 2.5 in | 1.53 | 15.28 | 9.17 |
| 3 in | 1.83 | 18.33 | 11.00 |
| 4 in | 2.44 | 24.44 | 14.67 |
Patches
Small repairs add up quickly in weight. A pothole cut out to 4 × 3 ft and filled 2 in deep takes 0.15 tons, about 300 lb, so cold patch from bags is usually the practical choice for a patch like that. For new paving, the base underneath matters as much as the asphalt; the gravel driveway calculator works out the stone.
Sources
- Maintenance Manual Volume 1, Appendix: Useful Information, California Department of Transportation, July 2014. Loose weights of crushed gravel, limestone, granite, screenings, sand and soil; 111 lb of asphalt mix per square yard per inch; 2.0 tons per compacted cubic yard of base.
- Highway Maintenance Tables and Conversion Factors (Engineering Policy Guide appendix), Missouri Department of Transportation, current guide. Loose and compacted weights of crushed stone, sand, asphalt and concrete in pounds per cubic foot and per cubic yard.