Gravel for a 20x40 driveway
At 3 inches deep, with a 5 percent allowance.
Cubic yards
7.78cu yd
Tons (approx)
10.89tons
cubic yards = 20 × 40 × (3 / 12) ÷ 27 × 1.05 = 7.78 cu yd
That is about 6.1 × 12.2 m, roughly 5.95 m³ at 8 cm deep.
Open the interactive Gravel CalculatorAbout this estimate
A 20 by 40 foot area at 3 inches is about 7.41 cubic yards before waste. Crushed gravel runs roughly 1.4 tons per cubic yard, though pea gravel and washed stone differ.
Spreading gravel? A contractor wheelbarrow makes short work of moving it from the pile.
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Common questions
How much gravel for a 20 by 40 driveway?
A 20 by 40 foot area at 3 inches deep needs about 7.78 cubic yards, roughly 10.89 tons of crushed gravel.
How deep should a gravel driveway be?
Three to four inches for a top layer over an existing base, more for a full build with a sub base. Confirm the stone density with your supplier.
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