Methodology and sources
Every calculator runs on tested formulas with exact unit conversions. Each one is checked against worked examples calculated by hand before it is published, and every default value lists where it comes from. Each typical published value is approved by a person before the site goes live, based on the sources listed beside it; values marked as our default are starting points you can change.
Results are estimates for planning and ordering, not professional, engineering or legal advice. Confirm quantities, sizes and local building requirements with your supplier or contractor before you buy or build.
Gravel calculator
| Value | Default | Type | Sources |
|---|
| Density of crushed stone / gravel (1/4"–2", loose) | 1.4 tons/cu yd (published range 1.4–1.7 tons/cu yd) | Typical published value | Billdr PROInch Calculator |
| Density of crusher run / road base | 1.5 tons/cu yd | Typical published value | Select Sand & GravelJ1S Contracting |
| Compaction and waste margin | 10 % | Our default (editable) | — |
Sod calculator
| Value | Default | Type | Sources |
|---|
| Area of a 16 × 24 in sod piece | 2.667 sq ft | Exact arithmetic | Sod Solutions |
| Waste margin for sod | 5 % | Our default (editable) | — |
| Sod coverage per pallet | 450 sq ft (published range 400–700 sq ft) | Typical published value | Sod Solutions |
Volunaro