Mould

Black, grey or brown spots on the painted surface.

Possible Cause

• 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 low quality latex paint.
• Failure to prime a bare wood surface before applying the paint.
• Painting over a substrate or coating on which mould or mildew has not been removed.

Solution

Test for mildew by applying a few drops of household bleach to the area; if it is bleached away, the discolouration is probably mould or 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 mould or mildew, use a premium water-based paint, and clean when necessary with bleach/detergent solution. Consider installing and exhaust fan in high moisture areas. 

Images courtesy of the Paint Quality Institute from Dow Coating Materials

Colourplus recommends Colourplus Ultra Premium Ultracare Satin Kitchen & Bathroom for wet areas such as kitchens, bathrooms and laundries.