Yakisugi
Yakisugi is a traditional Japanese method of wood preservation. It is also referred to as, a term which uses the same kanji characters, but an alternative pronunciation. The ban character means "plank". In the West, it is known as burnt timber cladding.
Process and properties
By partially charring the surface of the wood without combusting the entire piece, the surface becomes water-resistant through carbonization, and its hygroscopy is reduced due to chemical cellular changes during the carbonization process, which results in increased durability. It additionally protects the wood against insects, fungi and mold, as well as making the wood more fire-resistant. This traditional technique has several similarities with the modern thermal wood modification methods used in Europe and elsewhere.However, some studies have shown that surface charring alone does not improve its durability or its resistance to fire or water.