The effect of natural weathering on untreated wood surface

Abstract

As a result of contemporary ecological and sustainable movements, a number of constructions from wood, as the only renewable building material, is still increasing. In accordance with these trends, wood elements are often left untreated. The presented study is aimed to characterize and compare a surface degradation of untreated wood caused by weathering. Weathering characteristics of softwoods and hardwoods (spruce, pine, Douglas fir, larch, oak, black locust, maple, poplar and alder) during twelve months of exposure in the climatic conditions of Central Europe were determined. All the wood species were characterized by colour and gloss changes and increasing roughness. The lowest discoloration was observed for oak and the highest one for spruce wood, respectively. The lowest changes of roughness were observed for alder, the highest for spruce wood. The depth of colour changes was relatively similar among the softwoods. Regarding hardwoods, it varied more. The values of total colour changes had a significant correlation with the depth values of these colour changes. Maple, alder and poplar samples were characterized by the presence of mould and blue-stain fungi. Douglas fir wood was found to be the most liable for the formation of cracks.

Efficacy of Hydrophobic Coatings in Protecting Oak Wood Surfaces during Accelerated Weathering

“…This determines the oak wood to be suitable for outdoor applications that require high bio-resistance, without the need for impregnation with fungicides [55]. Nevertheless, it also quickly loses its original colour due to weathering [56], and proper surface treatment in the form of a coating system is thereby necessary in order to maintain its natural appearance. The application of coating systems is problematic due to the uneven structure and content of tannins [53], and therefore the service life of coatings is limited [57].…”

Surface properties of novel wood-based reinforced composites manufactured from crushed veneers and phenolic resins

“…Surface properties of the substrate have significant effects on the quality of final products laminated with thin overlays. A large amount of research had been made to study the surface properties of untreated wood (Oberhofnerová et al 2017), thermally compressed veneers (Aydin et al 2005, Bekhata and Krystofiak 2016, Candan et al 2010, overlaid particleboard and MDF (Büyüksarı 2013, Hiziroglu et al 2004, Hiziroglu and Zarate 2007, wood polypropylene composites (Bledzki et al 2010, Li 2014, Liu et al 2016, Liu et al 2010, Hutyrová et al 2014. The techniques to evaluate the surface roughness and surface stability were also investigated in the literature.…”

Comparison of Exterior Coatings Applied to Oak Wood as a Function of Natural and Artificial Weathering Exposure

“…The complex open vessel morphological structure of oak wood complicates the overall application of coatings. A photodegradation process of oak wood accompanied with significant discolouration and leaching of extractives from the surface takes place during the initial phases of outdoor exposure [6], more intensely in the heartwood zone [7], which leads to the need to protect oak wood by coatings to maintain its natural appearance.…”