About the Plaster Calculator
Plaster or render quantity for a wall area at any coat thickness, with sand and cement.
Also known as: rendering calculator, plastering quantity, skim coat calculator, stucco calculator.
How to use this calculator
- Enter area to plaster, coat thickness, type, waste allowance and the other fields.
- The result updates instantly as you type — press Calculate (or Enter) at any time.
- Review the breakdown shown under the main result.
- Use Copy result or Share to save the answer or send a link with your inputs.
Formula
volume = area × thickness × (1 + waste)
Worked example
Using the values pre-filled in the calculator above:
- Area to plaster = 50 m²
- Coat thickness = 12 mm
- Type: Gypsum plaster (bagged)
- Waste allowance = 15 %
- Price per bag = 10
the calculator returns:
- Plaster bags (25 kg): 25
- Plaster by weight: 621 kg
- Volume: 0.69 m³
- Coverage per bag: 2 m²