Materio

How much skim coat for a wall

Skim coat is counted in kilograms per square metre per millimetre of layer. Two thin layers rather than one thick one.

Step by step

  1. Work out the wall and ceiling area and take off the windows and doors. That area is the starting point for every layer.
  2. Take the bag's consumption: gypsum skim about 1 kg/m² per millimetre, polymer about 1.2 kg/m². Multiply by the layer thickness.
  3. Multiply by the number of layers and divide by the bag weight. Round up — you cannot buy part of a bag.

Calculators used in this guide

Paint, plaster, primer
Tip

On raw plaster the first layer goes on thicker than the label assumes, because it fills the unevenness. Count the first layer as 1.5 mm and the second as 0.5 mm, and prime first — without primer the skim pulls water out and dusts.

All guides

The same formula in the app Materio for Android uses the same engine offline — with the material catalogue and results saved into a project. Download