Frosting
 
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 the paint is exposed to excessive moisture (dew, condensation, rain, etc.) or cool temperatures during the curing process and create a surface condition called "frosting."
 
Solution

Apply paint to all surfaces during climatic conditions that allow proper curing of the paint film. If frosting occurs use a garden hose to flush crystal formations with warm tap water. Water-soluble crystals will disappear. Follow-up water flushing may be required at later dates and eventually crystal formation will cease. 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 undercoater will act as a barrier coat preventing the formation of future frosting. Apply latex or alkyd topcoat.

Caution: Wear a face mask to avoid inhalation of dust particles during the sanding procedure.

Note: Frosting may dissipate over time (several weeks or months)
 

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