Wood is a frequently used material. Timbers’ mechanical properties, particularly its favourable strength-to-mass ratio, make them suitable for many uses. Current environmental awareness has led to its renewed importance as a building material. However, wood is susceptible to decay that severely affect its outdoor performance. This study investigated how weathering affects the natural durability and moisture dynamics of six commercially important European wood species. Defect-free specimens (1.5 cm × 2.5 cm × 5.0 cm) were exposed to natural weathering for 9, 18, and 27 months or artificial accelerated weathering. The exposure corresponded to the 3rd use class (above ground, uncovered, frequent wetting). The moisture performance of control and exposed samples was then determined according to the Meyer-Veltrup approach. The same samples were also exposed to the brown-rot fungus Gloeophyllum trabeum for 16 weeks. The respective wood species were classified into durability classes according to EN 350, and the relative resistance dose (Drd rel) was calculated. Weathering reflected in decreased relative resistance dose, which can be attributed to leaching of biologically active extractives, altered surface morphology, and increased permeability. The most significant decreases were observed in the heartwood of sweet chestnut, Scots pine, and European larch. Moreover, a good correlation can be observed between mass loss after weathering, and mass loss caused by G. trabeum, especially in the heartwood of sweet chestnut was determined.

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