Chalking is the formation of fine powder on the surface of the paint film during weathering, which can cause colour fading. Although some degree of chalking is a normal, and is the expected way for a paint film to wear, excessive film erosion can result in heavy chalking which is never a good look.

Possible Cause

Generally there are some contributing factors that cause chalking;

  • Paint not applied at recommended spreading rate
  • the use of low-grade, highly pigmented paint or,
  • use of an interior paint for an outdoor application.

 

Solution

To eliminate the effect completely, the entire surface will need to be pressure washed and/or scrubbed with a non-metallic scouring pad to remove all surface contaminants and chalking prior to repainting.

 

Prevention

The use of a water based 100% acrylic latex topcoat provide superior exterior durability and gloss retention relative to many alternative coatings systems, especially oil based enamels. A number of Dulux® decorative paint products could be considered but for maximum gloss and colour retention, the Dulux Weathershield range provides the best performance.


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