Studies on the durability and moisture dynamics of contact charred softwoods

The construction industry accounts for a significant environmental impact; thus, it is vital to improve its environmental performance. This can be achieved using renewable, carbon-neutral materials like wood. Modified wood, an excellent outdoor material, faces limitations due to its high production costs. One alternative is surface charring, where wood is heated up to 450°C. This process changes the wood's surface, enhancing its properties, and has gained popularity recently. Charring, an ancient wood preservation technique, produces a distinctive black carbonised surface. Charring enhances wood's resistance to weathering and fungal degradation and increases its hydrophobicity. Within the respective study, researchers aimed to classify charred wood's durability using existing models based on its inherent durability and water exclusion efficacy. In the respective study, three wood species (Norway spruce, Scots pine and silver fir) underwent charring in the ranging between 300°C and 400°C. Charring led to mass loss and minor surface properties changes, such as roughness and contact angle. While charring influenced durability against fungi, it did not significantly affect liquid water uptake, and oil treatment further improved water resistance. These findings led to calculations predicting the wood's expected service life based on its resistance to decay and wetting ability. Charring positively impacted wood's resistance dose, indicating increased durability. Overall, the research delves into the impact of charring on wood properties, emphasising its potential to enhance wood's outdoor performance while offering insights into its limitations and strengths for sustainable construction practices. • Charring is a popular technique for wood modification. • Charring improves water exclusion efficacy and the inherent durability of wood. • Improved water performance and durability lead to prolonged service life of charred wood in outdoor applications.