To determine how much gravel you need, follow these steps:
- Measure the area you want to cover in feet (length × width).
- Decide the depth of gravel required, usually between 2 and 6 inches depending on the project.
- Convert depth inches to feet by dividing by 12 (e.g., 3 inches = 0.25 feet).
- Calculate volume in cubic feet : multiply length × width × depth (in feet).
- Convert cubic feet to cubic yards by dividing by 27 (since 1 cubic yard = 27 cubic feet).
- Estimate weight in tons (optional) by multiplying cubic yards by gravel density, typically about 1.4 tons per cubic yard for dry gravel.
Example:
For a 10 ft by 10 ft area with 2 inches depth:
- Depth in feet: 2 ÷ 12 = 0.166 ft
- Volume: 10 × 10 × 0.166 = 16.67 cubic feet
- Cubic yards: 16.67 ÷ 27 = 0.617 cubic yards
- Weight: 0.617 × 1.41 (density) ≈ 0.87 tons of gravel
Notes:
- Typical gravel depth varies by use:
- Driveways: 4-6 inches
- Garden paths: 2-4 inches
- Patios: 4-6 inches
- French drains: 8-24 inches
- For irregular shapes, break the area into simpler shapes, calculate each volume, then sum them
- Always round up to avoid running short
This method will give you a reliable estimate of how much gravel you need for your project.
