Mould is the black, grey or brown spots that can appear on the painted surface.

Possible cause

  • Mould forms most often on areas that tend to be damp, or receive little or no direct sunlight (e.g. bathrooms, kitchens and laundry rooms)
  • Use of flat or matt paints in areas subject to moisture
  • Use of low quality latex paint
  • Failure to prime a bare wood surface before applying the paint
  • Painting over a substrate or coating on which mildew has not been fully removed



Test for mildew by applying a few drops of household bleach to the area; if it is bleached away, the discolouration is probably mildew. Remove all mildew from the surface by scrubbing with a diluted household bleach solution (one part bleach, three parts water), while wearing rubber gloves and eye protection. Rinse thoroughly.

To protect against mildew, use a premium quality water-based paint, and clean when necessary with bleach/detergent solution. Consider installing an exhaust fan in high moisture areas.

If the area is subject to frequent moisture, e.g. bathrooms, consider using Wash&Wear® +PLUS Kitchen & Bathroom.

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