How much asphalt do I need for a 20x40 driveway?
Check it with your own numbers
Open the Asphalt Calculator with these values
| Length | 40 ft |
| Width | 20 ft |
| Compacted thickness | 3 in |
| Density | 145 lb/ft³ |
| Price per ton (optional) | 0 $ |
| Asphalt needed | 14.5 tons |
| Volume | 200 ft³ |
Tons of hot mix
A 20x40 driveway is 800 ft². At 3 inches compacted, that is 200 ft³. Compacted hot mix weighs about 145 lb per cubic foot, so 200 × 145 ÷ 2,000 = 14.5 tons.
Is 3 inches enough?
For a residential two-car driveway on a good base, 2 to 3 inches compacted is standard. Some contractors lay 2 inches of binder course plus 1.5 inches of surface course for a total of 3.5 inches. If you park an RV or a work truck, go to 4 inches.
The base matters more than the asphalt
Most driveway failures start underneath. Before paving, the 800 ft² should get:
- Topsoil and organic material dug out
- 6 to 8 inches of compacted crushed stone (about 15 to 20 tons of base for this driveway)
- Proof-rolling to find soft spots
Use our gravel calculator with the "Crusher run / base" setting to figure the stone.
Reading a paving quote
Pavers quote by the square foot, but ask how many tons they plan to lay. If a quote for this driveway is based on much less than 14 tons at 3 inches, either the thickness is thinner than promised or the math is off. Also ask:
- Compacted thickness, not loose. Loose asphalt is about 25% thicker before rolling.
- Whether the base work is included
- Edge treatment: a 45-degree tapered edge lasts longer than a vertical one
Timing
Hot mix needs air temps above about 50°F and a warm base. Most plants shut down for winter in the north. Book in spring or early fall.
Sealcoat
Wait 6 to 12 months before the first sealcoat, then reseal every 2 to 3 years.
For other sizes, use the full Asphalt Calculator or browse all answers.