Volume & Material Takeoff
Volume takeoffs tell you how much concrete, asphalt, base, or soil a job needs.
1 cubic yard = 27 cubic feet · concrete slab = L × W × thickness (ft) ÷ 27 · 1 cu yd at 4 in = 81 sq ft · asphalt tons = volume × unit weight ÷ 2,000 · always round up for waste.
Worked examples
- A 9 ft × 9 ft × 4 in slab = 9 × 9 × 0.333 = 27 cu ft = 1 cubic yard.
- A 12 ft × 18 ft × 6 in slab = 108 cu ft = 4 cubic yards.
- A trench 2 ft × 3 ft × 90 ft = 540 cu ft = 20 cubic yards of spoil.
- A 162 sq ft area at 4 in of base = 162 ÷ 81 = 2 cubic yards of aggregate.
Remember the 4-inch rule: one cubic yard spread 4 inches thick covers 81 square feet — a fast way to estimate slabs and base.
Practice: Volume & Material Takeoff
Frequently asked
How do you figure cubic yards of concrete for a slab?
How many square feet does a cubic yard of concrete cover?
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