Moisture Sorption of Wood Surfaces Modified by One-Sided Carbonization as an Alternative to Traditional Façade Coatings

Surface carbonization, or charring, of wooden cladding boards is a promising, low impact process that can substitute inorganic coatings. The char surface inert and hydrophobic possibly long-lasting solution for exterior uses. To determine the performance surface-charred wood, several sorption experiments were established. Sapwood two hardwoods (aspen, birch) softwoods (pine, spruce) used as experimental material, modified by contact charring gas flame including surfaces coated with oil further protection. results showed modification equal to double layer acrylic paint on primer in terms permeability all wood species, higher moisture exclusion efficiency at high relative humidity. Contact presented much improved properties comparison both implemented experiments, but dimensional stability was poor strong cupping wetting. However, especially birch exhibited less distortion than other investigated oiling reduced cupping. produced more repeatable from substrate species benefitted, whereas dependent inherent does not seem suit aspen well birch, pine spruce, although affected observed results.