Cause Frosting is the formation of white surface crystals on paint surfaces. When present, these crystals are most noticeable on dark colors and form in areas that are protected from the cleansing action of rainfall. The crystals form when trace impurities in the paint film chemically react with acid rain and create a surface condition called "frosting".
Solution Frosting is composed of crystals that are either soluble or insoluble in water. Using a garden hose, flush crystal formations with clean tap water. Water-soluble crystals will disappear. If crystals are not water-soluble, then other actions are required. Allow surface to dry thoroughly. Using medium grit sanding paper, lightly sand crystals away until original color of paint film reappears. Remove all loose dust and apply a uniform coat of A-100 Alkyd Wood Primer. This alkyd under-coater will act as a barrier coat preventing the formation of future frosting. Apply latex or alkyd topcoat.
