Yakisugi

Yakisugi (焼杉, lit. 'burnt cypress' ) is a traditional, very old Japanese method of wood preservation. It is referred to in the West as burnt timber cladding and is also available as shou sugi ban (焼杉板), a term which uses the same kanji characters, but an alternative pronunciation. The ban character means "plank".

By slightly charring the surface of the wood without combusting the whole piece, the wood becomes water-proof through the carbonisation and is thus more durable, however there is conflicting evidence that this method of wood preservation does not improve durability or fire resistance. It additionally protects the wood against insects, fungi and mold, as well as making the wood a rather fire-resistant material.

This old technique has several similarities with the modern, thermal wood modification methods used in Europe and elsewhere.

Examples
Contemporary architect Terunobu Fujimori  works with yakisugi. In addition, Japanese architect Kengo Kuma uses this charred wood material in his modern creations.