Estimate drainage stone for excavation dimensions you already have. Subtract chamber displacement to find the stone fill volume.
Your estimate
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Weight is an estimate. Stone grading, bulk density and moisture vary; confirm the product and order quantity with your supplier.
Enter the planned excavation dimensions and, for a chamber or crate, its dimensions. The calculator subtracts chamber displacement from the excavation volume to estimate the stone fill. Your allowance changes only the final stone quantity.
Excavation volume − chamber volume = net stone fill volume. The chamber is not counted as stone.
Drainage projects commonly use clean, washed stone. Follow the chamber manufacturer, installer, engineer or applicable local project requirements; no single stone type fits every installation.
No. This estimates stone quantity for dimensions you already have. It does not determine stormwater storage capacity, infiltration performance, soil suitability or code compliance.
An 8 × 8 ft excavation, 5 ft deep, with a 4 × 4 × 4 ft rectangular chamber and no allowance:
Enter the excavation and chamber dimensions. The estimate subtracts chamber displacement from excavation volume, then applies only the allowance you select.
No. It estimates stone quantity for dimensions you already have. It does not assess stormwater capacity, infiltration performance, soil conditions or code compliance.
No. Allowance is an optional extra for measurement differences and irregularities. It is not a compaction factor.
The chamber occupies part of the excavation, so stone fills only the remaining volume around it.