FIRED WOOD
Japanese ‘shou sugi ban’ technique chars, preserves, finishes boards
It looks like Andy Zeeck is playing with fire, but he’s actually wielding it like a paintbrush.
Using a propane weed torch to sweep flames down a plank of cedar, he demonstrates. The wood surface blackens and caramelizes under the heat — “cedar brulee,” as Zeeck jokingly puts it.
The smell of burning cedar hangs heavy in the air as he works.
Once he’s done, Zeeck puts aside the torch, grabs a brush out of a nearby bucket of water and scrubs it across the blackened wood as steam rises from the surface.
After the wood has cooled, he’ll brush away the loose ash and add a coat of tung oil to give the surface even more of a sheen.
Already, though, the surface has taken on depth
almost like lava rock, the sunlight catching glittering bands threading through the darkness. At other times, the same surface might take on a more matte appearance or the depth of the color may shift.
It all depends on the light.
“The thing I thought was fun about this is what you’re creating changes as the sun moves past you during the day,” he said. “Your one building detail may look one way in the morning and a different way in the evening.”
Just file it all under “old is new again.” Zeeck recently began experimenting with the centuries-old Japanese technique that preserves and finishes wood by charring its surface with fire. Known in the West as “shou sugi ban,” it’s making a comeback among Western designers and architects.
“It’s a counterintuitive but ingenious idea: heating wood to render it fireproof,” writer Amanda Fortini noted in The New York Times last fall. “If you’ve ever tried to rekindle a campfire using burned logs, you get the idea. The combustion also neutralizes the cellulose in the wood — the carbohydrates that termites, fungus and bacteria love — making it undesirable to pests and resistant to rot. The resulting charcoal layer repels water and prevents sun damage, as well.”
Something different
Across the country, people are charring everything from wood siding and flooring to furniture. For Zeeck, a green-forward builder and owner of Dwellings LLC, it’s a way to add a touch of flair to a home he’s building in the SOSA (South of St. Anthony) area.
“I was just looking for something a little different, and I always like simplicity,” Zeeck said. “This seems like a simple, natural way to solve your problem if you’re looking for a way to preserve wood.”
He’d said read about the technique somewhere, so he took to the internet to find out more about it.
“YouTube,” he said, laughing. “You figure if you want to do anything, someone’s on there to show you how.”
Cedar is the ideal wood, according to experts Architectural Digest sought out for a story last year, but other woods such as pine and oak work, as well.
Whatever the wood, Zeeck said each piece offers different results. Some of it comes down to the species.
“I did a pine, a yellow pine, and it’s a little harder and denser,” he said. “So if you keep the flame on it a bit, it comes out kind of like tiger skin, yellow and black.”
Variations within the wood itself also make a difference.
“The rings of the trees burn differently,” he said. “There’s a hard section and then a soft section. The soft burns faster.”
The results are patterns that can vary even among planks harvested from the same tree.
As decorative as it is, though, shou sugi ban also offers a way to preserve wood without having to coat it in chemicals.
“You don’t necessarily have to maintain it,” Zeeck said. “The charred wood doesn’t gray out.”
By some estimates, boards preserved this way can last 80 years or more, though one temple built with the shou sugi ban technique in Japan may date back to 711.
“You can stain wood like the way we did this fence,” Zeeck said, indicating the red-stained cedar fence enclosing the yard where he’d been working. “That’s about a two-year deal.”
He then tapped the board, now cooled and gleaming under a fresh coat of tung oil.
“Now this,” he said, “they say this will last forever, whatever forever means.”