How much asphalt to order
Asphalt plants sell hot mix asphalt by the ton, while driveways are measured in square feet and inches of thickness. The calculator converts the area and compacted thickness into tons, adds a margin for waste and edges, and estimates the cost of the material at your price per ton.
The formula
- Volume = length × width × compacted thickness
- Weight = volume × density; compacted hot mix asphalt weighs about 145 lb per cubic foot
- Tons = weight ÷ 2,000
A quick rule: 1 in of asphalt over 100 sq ft weighs about 0.6 ton.
Worked example
A driveway 50 ft long and 12 ft wide, paved with 3 in of compacted asphalt, at $130 per ton.
- Area: 50 × 12 = 600 sq ft.
- Volume: 600 × 0.25 ft = 150 cubic feet.
- Weight: 150 × 145 = 21,750 lb, plus 5% for waste and edges = 22,838 lb, or 11.4 tons.
- Material cost: 11.4 × $130 = $1,484, or about $2.47 per square foot.
Tonnage by thickness
For the same 600 sq ft driveway:
| Compacted thickness | Tons | Material cost |
|---|---|---|
| 2 in | 7.6 | $990 |
| 2.5 in | 9.5 | $1,237 |
| 3 in | 11.4 | $1,484 |
| 4 in | 15.2 | $1,979 |
| 6 in | 22.8 | $2,969 |
How thick should it be
- Residential driveways: 2 to 3 in of compacted surface course on 6 to 8 in of compacted crushed stone base.
- Heavier traffic (RVs, delivery trucks): 4 in or more, often in two lifts, a binder course and a surface course.
- Parking lots: typically 3 to 4 in over a deeper base, designed for the expected traffic.
Asphalt is laid loose about 25% thicker than its final thickness and rolled down; order based on the compacted thickness.
What the price per ton covers
The plant price is for the material only. An installed driveway also includes excavation, base gravel, grading, hauling, paving equipment and labor, which usually cost more than the asphalt itself. Ask contractors to state the compacted thickness of the base and the asphalt in the quote, so you can compare bids. New asphalt should cure for a few days before you drive on it, and many contractors recommend a sealcoat after six to twelve months.