To prolong the service life of a wooden construction the protective function of a coating is of utmost importance. The chemical composition as well as the wood-coating interface affects the performance of this protective layer and obviously wood species have an impact too. This paper discusses the influence of wood species on the overall coating performance. Therefore, a range of opaque waterborne acrylic coatings applied on industrially finished window frames made of frequently used commercial hardwood and softwood species were tested. Both, artificial and natural weathering, were considered for the durability assessment. Complementary studies on moisture dynamics and fungal growth were included as well. Coatings applied on dense tropical hardwood with large vessels perform fairly well in regard to water related failure, but erosion or weathering phenomena occur early. The opposite is true when examining small or medium porous hardwoods. Coatings applied on softwood substrates performed the worst. Yet, in contrast to hardwood, the performance of softwood based systems under laboratory test conditions is less correlated with outdoor performance.

Download document (445 kb)
free for the members of IRG. Available if purchased.

Purchase this document