No. 7 Stone Calculator
Enter the size and depth of the area. The calculator uses the loose weight of No. 7 stone (1.40 tons per cubic yard); change it to your quarry's figure.
Enter your numbers and press Calculate.
Working it out
Tons = length × width (ft) × depth (in) ÷ 12 ÷ 27 × 1.40
Example: 20 × 10 ft at 4 inches is 2.47 cubic yards. At FHWA's loose weight that is 3.44 tons; packed dense it would weigh 4.03 tons.
| Depth | Sq ft per cu yd | Sq ft per ton |
|---|---|---|
| 2 in | 162 | 99 to 116 |
| 3 in | 108 | 66 to 77 |
| 4 in | 81 | 50 to 58 |
| 6 in | 54 | 33 to 39 |
Per-ton range runs from dense (1.63 t/yd³) to loose (1.40 t/yd³).
Size of No. 7
No. 7 is 1/2 in to No. 4. See the full gradation for the sieve limits.
Common questions
How many tons of No. 7 stone do I need for 100 sq ft at 4 inches?
1.23 cubic yards, which is 1.72 to 2.01 tons.
Related calculators
Sources
- https://www.fhwa.dot.gov/publications/research/infrastructure/structures/bridge/15034/003.cfm
- https://spinternet.dot.state.oh.us/Divisions/ConstructionMgt/OnlineDocs/Specifications/2005CMS/700/703.htm