Why do you want to burn my office?
My builder, David, wants to set fire to the wood he’s planning to build my office with! Apparently it is a technique used in Japan called Shou Sugi Ban (no I don’t know how to pronounce it). It translates to burnt cedar board.
I’ve done a bit of research. (I’ll ask David if he has a photo I can have)
Originally, Japanese carpenters enjoyed using recovered driftwood they found as it’s more durable, whilst still having a unique artistic finish. Driftwood has been through a weathering process that gives it a unique appearance and durability.
But there wasn’t much of it.
So the Japanese turned to another natural process to get the same look and durability. In this case fire. They’ve been doing it in Japan since the 1700’s at least. Modern plastic or cement based decking and fencing has become more popular over the past 50–100 years, partly because there isn’t much wood in Japan now so they have to import it making it more expensive.
In the early 2000’s, Shou Sugi Ban was rediscovered, first in Japan and then by other people building custom designed houses and buildings.
It has the properties of being bug and pest resistant (although not bug proof) and also, strangely, fire resistant.
It seems that wood is made of two parts; there’s the cellulose which is how the tree starts out with the flexibleness of a young sapling, plus the leaves are also cellulose. Then there is lignin which is hard and brittle. Old tree trunks have lots of this.
When you char wood the cellulose gets burned off but the lignin takes a longer time to burn so is left behind when the fire is put out. This lignin needs a higher temperature to burn so is harder to ignite again. Maybe it is like trying to burn oak, you need a high heat to get it started and oak is super hard. Also the outer layer of charred wood acts as an insulator.
One of the websites call it the wood equivalent of weathering steel and says it is also rot resistant and even UV resistant.
All this means there is no need for chemical preservative or paint. Apparently, this means the wood lasts for 80–100 years virtually maintenance free.
Problem is I’m not sure I want a black office building..
