Last year, a client came to us with a photo of a Japanese engawa (roofed porch). The engawa and all the woodwork looked very old and very dark, as if decades or maybe centuries of sun and weather had worn the wood and the wood had turned a rich dark brown color.Perhaps it was helped with a stain, or maybe the carpenters had used this same technique, but it was quite beautiful never the less.
We had just finished the main timber frame for his house and we were just getting started cutting all the exterior timber work for his house. He told us that he wanted all the exterior timber to look like the wood in the photo. After looking at the photo for awhile, I remembered reading about an old technique of burning wood for a more weather resistant finish. After doing a bit of research, I ran across the term “Shou Sugi Ban”, which translates roughly to Burnt Cedar Siding. I told the client that we may be able to get the same look using this technique and that we would make up some samples for him.
After a bit of trial and error, we worked out a system that we think works well, and produces a gorgeous finish that you couldn’t get any other way.
The method we worked basically involves 4 steps. First we “torch” the wood, which leaves a layer of char or soot on the surface of the timber. Torching the wood achieves two main things. First, the early wood burns quicker than the harder late wood so that when scrubbed off, more early wood has been removed so you end up with a beautiful “weathered” texture. Secondly, the fire and heat don’t penetrate into the wood very far so that beneath the soot, a layer is created where the wood has been heated to such a degree, but hasn’t actually burnt, that it turns a rich chocolate brown color. The late wood burns at a higher temperature than the early wood so it ends up being darker. This creates a look that is opposite to what you would get by using a stain.
After torching, we scrub the soot off using water and a stiff bristle floor scrub brush. We tried a wire brush but found it was too course and would scratch the colored layer just below the soot. Once most of the soot has been scrubbed and rinsed off, we move the timber indoors and do a final cleaning using wet rags to buff and polish out more soot. Finally we oil the timbers using a natural clear finishing oil.
Shou Sugi Ban is a gorgeous, unique finish that gives wood the appearance of being centuries old and a color that we believe no stain can match.