Problem - Chalking
Formation of chalky powder on the paint film surface. Over time, all paints will show some chalking.

Possible causes

  • Previous use of alkyd or oil paint.
  • Chalking is especially prevalent with dark or bright colours.
  • The paint was tinted with an unsuitable colourant, or with too much colourant.


If the surface does not require repainting, remove mould with Tikkurila Huoltopesu as instructed on the product label and rinse thoroughly.

If the surface is to be repainted, remove mould with a solution of Tikkurila Homeenpoisto, 1 part to 3 parts water. Protect yourself and your plants, glass surfaces, etc. from splashing. Clean with a sponge or a soft brush. Wash larger surfaces with a portable sprayer. Spray the solution upwards to avoid seeping or streaks. Let the solution take effect for about 30 minutes. Surfaces badly affected by mould should be left wet until removed completely. Wash from the top downwards using plenty of water.

Allow to dry. Paint with a suitable Tikkurila exterior paint. Acrylate paints are less chalky than oil paints.