This handy tool will help you to work out the tonnage required for your job. To use it simply follow these easy steps:

1. Type in the width, length and thickness of the area you want to cover
2. Click on inches or feet according to your measurements
3. Click on either Base Rock, Drain Rock or a custom density selection. If you select Base Rock or Drain Rock the density of the rock will automatically fill in. The Custom Density selection allows you to enter your own density.
4. Finally, click on the Calculate button. The calculator will work out how many tons are required.

Please note that densities will vary from load to load but the default values assigned for Base Rock and Drain Rock are good 'rules of thumb' for estimating. For an exact calculation, we recommend you contact an engineer.