Black, gray, green, or brown spots on any surface. The paint itself will not cause mildew but in certain atmospheres, mildew can appear on paint. 

• Mildew forms on interior and exterior surfaces such as walls and ceilings that tend to be damp or receive little or no direct sunlight.
• Mildew will persist if you paint over a painted surface containing mildew.

• Test for mildew by applying a few drops of household bleach to the area, if it is bleached away, the discoloration is probably mildew; if it does not disappear, it is probably dirt.
• Before painting a surface, you must remove any mildew. Start by washing the surface with a solution of one part liquid bleach and three parts water. Apply the solution and scrub the mildewed area. Allow the solution to remain on the surface for 10 minutes. Rinse thoroughly with water and allow the surface to dry before painting. Wear protective eyewear, protective clothing, and waterproof gloves. Quickly wash off any of the mixture that comes in contact with your skin. Do not add detergents or ammonia to the bleach/water solution.
• To protect against mildew, use a top-quality paint, and clean when necessary. Install an exhaust fan in high-moisture areas.
• Use products that contain agents that inhibit the growth of mildew on the surface of the paint film.
• If mildew is the only problem, re-painting may not be necessary after cleaning the surface. Use a cleaning solution that is safe to use on painted surfaces. Using bleach can cause color damage, so it is not always recommended unless you are repainting.

If you decide to repaint after removing the mildew, choosing high-quality paint products will help keep it at bay. Start with Premium Wall & Wood Primer. Then finish with SuperPaint Interior Acrylic with Air Purifying Technology, which can contribute to cleaner indoor air quality.

For repaint exterior projects, start with exceptionally durable Multi-Purpose Latex Primer. Or jump right in with self-priming Duration^® Exterior Acrylic Latex, a mildew-resistance coating.