TANNIN BLEEDING
TANNIN BLEEDING The brown or tan discoloration on a painted surface, most commonly observed over knots in certain types of timber (eg. Merbau, Western Red Cedar, Meranti).
POSSIBLE CAUSES • The use of a coating with poor stain blocking properties. • Excess moisture in the substrate. • Poor conditions during the application or drying period (eg. low temperatures, humid conditions, condensation, rain or dew).
SOLUTIONS • Determine and eliminate the source of moisture and repaint with a stain blocking primer or top coat once the surface is clean and sound. • Ensure application and drying conditions conform to manufacturer’s recommendations.
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