Perched on the slope of Cougar Mountain, Washington, just 20 miles southeast of Seattle, this house represents the new standard of sustainable home building—inside and out. Constructed to passive house standards, the design prioritizes energy efficiency and sustainability, which is reflected in its carefully chosen material palette.
A standout feature is Nakamoto Forestry's carbon-negative yakisugi cladding. Often referred to as ‘shou sugi ban’ in the West, yakisugi is made from Japanese cedar, or ‘sugi,’ that undergoes an intense burning process as a preservative heat treatment. This traditional technique significantly enhances the wood’s resistance to rot, pests, fire, and ultraviolet (UV) damage—qualities that are essential for a home situated in Washington's moist and wildfire-prone climate.
Architect John Novak of Velocipede Architects reflected on his choice to use Nakamoto Forestry’s yakisugi on the home’s exterior. “I had worked with Nakamoto's yakisugi on a previous project,” said Novak. “It’s a great product in terms of sustainability and durability, and it has a beautiful, natural texture.”
Novak selected Nakamoto’s Gendai yakisugi, which is lightly brushed after charring to remove soot, resulting in a smooth, dark finish that accentuates the wood’s natural grain. To further protect against UV damage and enhance color longevity, a dark gray alkyd oil stain was applied.
“The wood’s depth and darkness blend in with the surrounding nature,” said Novak. “That was our intent. We didn’t want the building to compete with the vegetation—we wanted it to be a backdrop to nature.”
Jon Alexander and his team at Sunshine Construction expertly installed the yakisugi cladding, positioning it vertically to reflect the tall trunks of the dense emerald forest surrounding the house. To enhance the cladding’s longevity, Alexander incorporated a rainscreen beneath the siding, which allows trapped moisture to drain or evaporate quickly. With proper manufacturing and installation, authentic yakisugi is estimated to last as long as 80 to 150 years without any maintenance—an exceptional lifespan for a natural, non-engineered material.
“When I build a house like this, my goal is that the house will last 200 years or more,” said Alexander. “I think the siding is an excellent product for covering the skin of it.”
With an oil finish, Nakamoto’s Gendai yakisugi is also suitable for interior use, which presented Novak with the opportunity to draw a throughline from the exterior to the interior. He chose to wrap the kitchen pantry in the richly textured wood, dramatically contrasting the otherwise bright interior.
“Our decision to use yakisugi was as much an aesthetic choice as it was a sustainability choice,” said Novak. “It was important to me—and to the homeowners—to use products that were durable and could withstand the test of time.”
The sustainability of yakisugi goes beyond its performance. Nakamoto Forestry sources its wood from sustainably managed timberlands in Western Japan, employing selective thinning techniques to maintain forest health. After harvesting, the wood undergoes air drying followed by flash burning, a process that is more efficient than traditional kiln drying.
For more information on the benefits of yakisugi, visit nakamotoforestry.com.
