Mill Glaze

Although there is some controversy regarding its cause, the most commonly held theory about the formation of mill glaze is that it is created on logs, siding and trim by heat and mechanical compression generated during a high speed milling process.  The combination of compressed wood fibers and high temperatures that melt the sugars and other water-soluble extractives present in the wood end up forming a surface glaze.  If not removed, this glaze can interfere with the adhesion of both water and oil-based coatings since the woods cellular surface is not in direct contact with the coating.

In actual practice pressure washing with Log Wash will remove most cases of exterior mill glaze.  However, if pressure washing is not an option, a good cleaning with Wood ReNew will work. For interior situations a light sanding followed by rinsing the walls with warm to hot water will help swell and decompress the wood fibers and dissolve the glaze, thus assuring the adhesion of our finishes to the surface of the wood.