Shou Sugi Ban procedure 1

[dik]

Recently, I’ve come across a finish treatment called ‘Shou Sugi Ban’. It was developed in Japan and consists of finishing exterior wood surfaces with a light ‘char’. This apparently provides a durable surface.

The improvements include making the surface more water resistand by closing open pores.

It also improves the insect and rot resistance. This includes improving the termite resistance.

It also improves the wood against external elements like sun and rain.

The charred surface apparently improves fire resistance. This latter item is surprising, since I was under the impression that prior char makes lumber more susceptible to fire damage.

Is anyone aware of this process and can anyone add additional information or confirmation of these enhancements.

 

[ctopher]

I watch HGTV and YouTube all the time. There are a few videos using this technique. I have not tried it.
I once knew a guy that tried it and the wood popped. A pocket of sap inside the wood heated up and popped. So wear protection if trying it.

 

[phamENG]

I'm aware of it - have a family member that had planned to use it as their siding, but never got around to the project. It was at its height of popularity around here 8 or 9 years ago. Don't hear much about it anymore, though it pops up every now and then. I seem to recall it being very expensive and difficult to source.

 

[hemiv]

I've encountered it in the timber framing world - you may find some more information through the Timber Framers Guild.

 

[jayrod12]

If you dig into fire rating of heavy timber, the char layer develops and then provides protection for the remainder of the wood. So there's some credence to improving fire resistance by providing an intentional char layer on the materials.

 

[dik]

If you dig into fire rating of heavy timber

I was aware of that... Mass timber can develop protection. I understand the char layer also makes the next exposure to fire easier even though it offers protection. The treatment is generally used for dimensioned lumber and cladding not mass timber.