Castable Quantity Calculator
Enter the lining size and the density from the data sheet. The calculator gives the kilograms, tonnes and number of bags to order, with a wastage allowance.
Quantity needed
Enter the lining dimensions and the material required per cubic metre to see the quantity.
Get a quote for this quantityHow the calculation works
Quantity (kg) = lining volume (m³) × material required (kg/m³) × (1 + wastage). For a flat wall, roof or floor the volume is length × width × thickness. For a cylinder it is the ring between the shell and the hot face: π × (shell radius² − hot face radius²) × height.
The same method works for gunning mixes and ramming mass. Anchors, formwork and bricks are not included. For installation steps and the dry-out schedule, see the castable installation guide. For grades, see low cement castables, conventional castables and insulating castables.
Questions about castable quantity
How do I calculate how much castable I need?
Multiply the lining volume in cubic metres by the material required in kilograms per cubic metre from the data sheet, then add a wastage allowance. Lining volume is area times thickness for a flat wall, or the ring volume between the shell and the hot face for a cylinder.
How much castable is needed per cubic metre?
It depends on the grade. Each data sheet states the material required per cubic metre or the bulk density. Dense castables need more kilograms per cubic metre than insulating castables, so always use the figure for the grade you are buying.
How much wastage should I allow?
This calculator starts at 5%. Allow more for gunning, where rebound loss is higher, and for small or awkward pours. Use the figure your installer works to.