How to Figure Asphalt Tons for an L-Shaped Driveway

Split an L into two rectangles, then subtract the shared corner once. A 12 by 40 leg plus a 20 by 12 spur, minus a 12 by 12 corner, is 576 square feet. At three inches that is about 10.4 tons before waste.

Open free asphalt tonnage calculator →

Count the corner one time

An L is two rectangles that share a square. If you add both full rectangles, you weigh the corner twice and the order runs high. Measure each leg to the outside of the pavement. In the planning example, one leg is 12 by 40, which is 480 square feet. The spur is 20 by 12, which is 240 square feet. The shared corner is 12 by 12, which is 144 square feet. Add 480 and 240 to get 720, then subtract 144 to get 576 square feet. Sketch the two boxes and hatch the corner so you can see that it sat in both measurements. Odd offsets and a curved fillet are extra shapes. Measure those on their own and add them after the L is clean.

Turn 576 square feet into tons

At three inches, tons equal 576 times 3 times 145 divided by 24,000. That is 250,560 divided by 24,000, which is 10.44, or about 10.4 tons. At two inches the same area is two-thirds of that depth, about 7.0 tons, because 576 times 2 times 145 divided by 24,000 is 6.96. Pick one compacted thickness and stay with it. The 10.4 is before waste, edges, and a flare at the street. This is a planning estimate at 145 pounds per cubic foot of compacted hot mix. The plant ticket is the real weight. If the plant prints a different density, replace 145 and multiply again. Do not subtract the corner a second time after you have already used 576.

Measure to the outside edge

Tape to the outside of the pavement you will place, not to the grass you hope will hide the edge. A leg that widens near the garage is a trapezoid, not a second excuse to ignore the corner rule. Average the widths for that piece, compute its area, and still subtract any overlap with the other leg. Then walk the L and see whether a paver can reach both legs or whether one leg is all rake work. Hand work can place the edge thicker than the formula. After the job, compare ticket tons with the 576 square feet, or with a remeasure if the built shape changed. The drawing is the plan. The scale is the weight.

A practical sequence

Measure each leg as a rectangle to the outside of the pavement.
Subtract the shared corner once so it is not in both areas.
Multiply the net square feet by inches, then by 145, and divide by 24,000.
Treat about 10.4 tons at three inches on this example as a planning estimate and check the plant ticket.

The mistake to skip

Adding both rectangles and leaving the shared corner in the area twice.

Questions people ask

What is the sample L in tons?

The sample is 480 square feet plus 240 square feet, minus a 144 square foot corner, which equals 576 square feet. At three inches, 576 times 3 times 145 divided by 24,000 is about 10.4 tons before waste. That is a planning estimate. The plant ticket is the real weight.

What if my L has a different width on each leg?

Use each leg's own width. Subtract only the rectangle that truly belongs to both legs. If the widths differ, the overlap is the narrower crossing, not a guessed square. Draw it, compute each area, and convert the net square feet to tons at one thickness.

As an Amazon Associate, AsphaltTons.com earns from qualifying purchases. Product links below are sponsored.