By slightly charring the surface of the wood without combusting the whole piece, the surface becomes water-resistant through the carbonization and at the same time its hygroscopy is decreased due to chemical cell-changing process during carbonization, which results in increased durability. [4][5] It additionally protects the wood against insects, fungi and mold, as well as making the wood a rather fire-resistant material.[6]
However, some studies showed that a mere charring of the surface does not improve durability or fire resistance. It also doesn't make the wood waterproof.[7]
This old technique has several similarities with the modern thermal wood modification[8] methods used in Europe and elsewhere.
Examples
Contemporary architect Terunobu Fujimori works with yakisugi.[9][10] In addition, Japanese architect Kengo Kuma uses this charred wood material in his modern creations.[11]