Plaster and filler calculator

Count the dry mix for levelling walls: gypsum or cement plaster, base or finishing filler.

tA
Letters on the drawing match the letters next to the inputs.
m²
mm
kg
More settings
%
Dry mix187 kg

Shopping list

  • Bags7 bags of 30 kg

How we got there

Consumption used
0.85 kg/m² per mm
Per area
8.5 kg/m²

Results are estimates. Always check the consumption printed on the product you buy.

How it is calculated

The amount of dry mix depends on the area, the average thickness of the layer and the consumption of the product per square metre for each millimetre. Typical values are used by default: 0.85 kg for gypsum plaster, 1.7 kg for cement-lime plaster, 1.0 kg for base filler and 1.1 kg for finishing filler. If your product states a different number, choose “Other” and enter it.

FormulaDry mix, kg = area × thickness (mm) × consumption (kg/m² per mm) × (1 + reserve)Bags = dry mix ÷ bag weight, rounded up

Example

20 m² of wall levelled with gypsum plaster at an average of 10 mm needs about 187 kg with a 10 % reserve — 7 bags of 30 kg.

Tips from practice

  • Measure the thickness with a long level in several places and use the average, not the thinnest point.
  • Layers over 30 mm of gypsum plaster usually need mesh or two passes.
  • Finishing filler is applied in 1–2 mm layers, so enter 1 or 2 mm.

Questions and answers

How much gypsum plaster per m² for a 10 mm layer?

About 8.5 kg per square metre. The calculator uses 0.85 kg per mm unless you enter your own value.

What is the difference between plaster and filler?

Plaster levels walls in thick layers, from about 5 to 30 mm. Filler is for thin layers, from fractions of a millimetre to a few millimetres, before painting or wallpapering.

Why is cement plaster so heavy?

Cement-sand mixes are denser than gypsum, so the same layer weighs about twice as much.

Found a mistake in a formula? Write to contact@planicalc.com