Natural weathering performance of exterior wood coatings on Pinus sylvestris and Pinus radiata in Germany and New Zealand

The weathering of commercial coatings on pine sapwood in Germany and New Zealand was studied. The New Zealand site had a climatic index 50 % more challenging. Significant differences in performance relating to coating, species, site, and exposure are presented. The coating and site had the most significant effects, while species had the least. A solventborne stain and a hybrid paint qualified for stable end-use situations in both countries. An acrylic paint performed better in Germany while an alkyd gave the poorest performance of the four coatings tested. More effective fungicidal coating properties are required in New Zealand to suppress mold growth. Areas of deficiency for internationalizing the European weathering standard EN 927 are discussed.