DRAINAGE CALCULATOR
Aggregate volume
What volume does a rectangular layer or trench occupy?
The calculation.
Cubic feet = length × width × (depth inches ÷ 12). Cubic yards = cubic feet ÷ 27.
A worked example.
20 ft × 2 ft × (6 inches ÷ 12) = 20 cubic feet, or about 0.741 cubic yards.
What the number means.
This is the geometric volume of a rectangular space. It does not deduct pipe displacement or add compaction, settlement, irregular excavation or delivery allowances. Material weight requires a separately verified density.
