“Yakisugi” or “Shou Sugi Ban”? Learn What You Should Call It, and Why

When we started researching the North American and European heat-treated wood market a few years ago we found that the word “shou sugi ban” has been incorrectly used in the West since at least the oughts in place of the original Japanese term “yakisugi”. Along with clarifying what the Japanese heat-treatment characteristics, specifications, and applications are, we would like to correct what our product is linguistically called as well. This starts with a little research into where the mis-reading originated followed by a technical explanation of the linguistic confusion.

On a trip to Japan late 2018 I met with the Japanese historian and architect Terunobu Fujimori to ask for guidance on his vision of presenting yakisugi to the West. Professor Fujimori has been active in introducing the technology to the international design world. He loves the beautiful black color, the vernacular, organic origin, and the transformative drama of fire in the manufacturing process. He brought up the term “shou sugi ban” and after having a good laugh we agreed that I should encourage correcting the term as part of our product education program overseas.

Professor Fujimori told me that “shou sugi ban” was likely a mis-reading by one of Cal Berkeley Professor Dana Buntrock’s graduate students around 10 years ago. Professor Buntrock was not sure about this when I asked, and thought that Harvard GSD Professor Toshiko Mori might know more. Professor Mori was not sure of the word’s origin either (blog readers, please email us if you know more!).

The Misreading of “Yakisugi” as “Shou Sugi Ban” Comes from a Difference Between Chinese and Japanese Languages

Along with Buddhism, poetry, and other mainland culture, the Chinese written language was first brought to Japan and adopted over a period of centuries, especially during the rule of Prince Shotoku Taishi at the start of the 7th century CE. Over the past 1200+ years the Japanese written language has been developed with the original Chinese characters called「漢字」or “kanji” as the written language core alphabet. Kanji can also be compared to Latin and Greek word roots used in English or other languages since they are strung together to make compound words.

Kanji are now one of three standard alphabets mixed together contextually to write modern Japanese. 「ひらがな」hiragana and 「カタカナ」katakana are the other two subsequently developed, indigenous Japanese alphabets that are combined with kanji into the modern written language. To give you an idea of scale, in the Japanese standard education system there are about 2,000 kanji, 100 hiragana, and 100 katakana taught to children for general literacy in daily life.

During the medieval period, to adapt the written Chinese language into Japanese use, the two languages were combined and kanji were given Chinese AND Japanese phonetic readings or pronunciations depending on context. Nowadays words can be written with kanji only, kanji and hiragana mixed, hiragana only, or katakana only, depending on context as well as meaning. Some of the most commonly used kanji have 20 or more different readings or pronunciations depending on context, since kanji are symbols with meaning(s) and not simply phonetic letters as in the other alphabets.

In other words a kanji will have a different pronunciation depending on which word it is used in. In general, when kanji are used together in a multi-kanji compound word originating from Chinese, then the Chinese pronunciation is used. And when the kanji is used independently as an indigenous Japanese word then it has the Japanese pronunciation. Add the Roman alphabet and Arabic numerals to kanji, hiragana, and katakana, and voila, the painful puzzle of reading modern Japanese.  This is the reason that so many foreigners can speak the language but very few can actually read and write it fluently.

So specifically what does this background mean in terms of calling the heat-treated siding “yakisugi” or “shou sugi ban”?  In Japanese colloquial as well as formal industry terminology our product is called「焼杉」or “yakisugi”, written with two Chinese kanji and pronounced with the Japanese phonetic pronunciation even though it is a compound word. It might be a compound kanji word with an indigenous reading due to specifically being a Japanese technology or maybe due to the material’s vernacular origin, but nobody really knows. 「焼杉板」is how the word is sometimes written, with a third kanji added to make the word “yakisugi-ita”.

「焼」or “yaki” means burnt, fried, grilled, heat-treated, etc. and is a general descriptive term. 「杉」or “sugi” means cypress as in Cryptomeria japonica, also called Japanese Cedar in the West.「板」or “ita” means plank or board. So「焼杉板」or “yakisugi-ita” translates into English as “heat-treated cypress board”, “burnt cedar plank”, etc.

The kanji「焼」or “yaki” by the indigenous Japanese pronunciation is read as “shou” in the Japanese pronunciation of the original Chinese pronunciation, also written as “xiao” in modern Mandarin Pinyin. Then「板」or “ita” by the indigenous Japanese pronunciation is read as “ban” in the Japanese pronunciation of the original Chinese pronunciation, similar to “ban” in modern Mandarin Pinyin. So somewhere along the line, most likely an academic (due to the less-often used compound 3-kanji word) mistakenly read 「焼杉板」 as “shousugiban” instead of the correct “yakisugi-ita”, or more commonly used “yakisugi”.  In other words the mistake a foreigner made was to read the compound kanji with a mixture of Chinese and Japanese pronunciations, instead of only the Japanese pronunciation that every Japanese person is familiar with.

People have been heat treating wood since prehistoric times, whether hardening spear tips, digging sticks, or throwing sticks, or burning boat hulls and exterior siding. We’ve found evidence going back 400,000 years in the archeological record. There are many local versions of heat-treated wood throughout the world. I have heard that there is burned siding in China, Korea, Eastern Europe, and Portugal, not to mention thermally modified wood by the Finnish process that is becoming popular worldwide in exterior applications. There is also high-heat carbonized wood from China, whiskey barrels from the European islands, wine barrels from France, and fence posts burned to slow down rot in many locations around the world.

So what does it matter whether it is called “yakisugi” or “shou sugi ban”?

Heat treating wood is a standard universal human technology, not a pseudo-Japanese surface burning treatment applied whimsically.  The Japanese heat treated wood is called “yakisugi” and it is thin plank porous cypress used in wall, fence, and ceiling applications only. We would like for Japanese wood burning technology to be understood better in the West since it has so much value in modern construction, and not misunderstood or mis-applied precipitating a negative reputation in our market niche. We want yakisugi to be appreciated for it’s improved longevity and fire resistance in the western market, as a healthy, sustainable, and beautiful building material option.  We would like to see only good quality yakisugi on the market, whether made by us, another mill, or on the jobsite.  This starts by calling it by its correct name, “yakisugi”, to avoid confusion with other heat treatment technologies or artistic wood burning applications popular today.