This sounds radical, but is an ancient practice that serves a purpose, and it is coming into favour in North America. In Japanese building, charring wood surfaces is known as yakasugi; this technique is valued because it wraps up wood in a layer of carbon that’s highly resistant to mould, insects, water and even fire. It also creates a powerful visual effect.

“It’s a beautiful way to get a dark brown that looks like tree bark, and a far more interesting way to get it than with staining the wood,” explains D’Arcy Jones, the Vancouver designer who created the Okanagan house. “The beauty of the wood is exaggerated.”

And since the region around the house experiences wildfires, the added fire-resistance of the charred skin is a comfort to the owners. (The exterior also features expanses of concrete block and cold-rolled steel.) The Friesens used a small propane torch to set fire to each 1-by-8-inch board, let it char to a medium brown, and then doused it with water. They brushed the surfaces, to remove the soot and achieve a smoother texture, to different degrees on different parts of the house (the surfaces that people can touch got a smoother finish). “It took love and elbow grease to do this,” Jones says. “And when it’s done, you have changed the structure of the wood forever.”

This provides a permanence that other, more quotidian wood treatments cannot match. Stain and paint will fade in time, whereas charred wood surfaces can last decades more or less intact. In Japan, this effect has traditionally been achieved with burning wood – cypress and more recently cedar – over an open flame, and sometimes adding an oil finish. The Japanese architect and historian Terunobu Fujimori has used this device prominently on his own buildings, which riff on Japanese historical precedents.

In the West, there have been relatively few uses of the technique until the past few years. The singular Swiss architect Peter Zumthor used a variation on it for his Bruder Klaus Field Chapel, a tiny, eccentric building in rural Germany, where a wood structure was built as a mould for poured concrete and then burned, leaving its charred traces on the inside.

“In Japan [charring] was used to preserve, but for me it was part of creating a slightly morbid narrative,” says designer Deborah Moss of Toronto studio Moss & Lam, which specializes in furniture and installations that fuse fine art and design. Moss & Lam used charring in creating its Torched Wood Screens, hand-carved wooden screens that depict street maps of five global cities (Paris, London, Berlin, New York and Tokyo) and are charred and sealed. “Maps are made of paper and they are ephemeral,” Moss says. “Charring, to me, suggested time passing. It’s as though you are holding an old, burned map.”

That said, the handcraft and the sheer, messy physicality of the wood make it feel slightly personal. “It’s a real material, and a material that has so much resonance to it,” Moss says. “When you see a piece of torched wood, it can be terrifying, but it has a life to it.”

In Vancouver, Jones agrees that charred surfaces in a home can have an unsettling effect. But this is something that he and his clients are willing to embrace. “Rooms are much more humane,” he says, “when there’s a bit of darkness around.”

Burnt House is an extension to a Victorian house in Fulham featuring a charred wood window seat and gridded glazing.

Its design is based on the shoji screen, a facade or room divider in traditional Japanese architecture and a common feature in the tea house.

“The concept of drawing inspiration from Japanese architecture materialised from the clients’ desire to use charred timber somewhere in the proposal,” explained architect and studio founder Will Gamble.

“The charring of timber is a traditional Japanese method of treating wood, therefore we felt that this Japanese influence should be reflected in the overall appearance of the scheme, not just its timber cladding,” he told us.

The clients, a young couple, had asked both Gamble and interior design studio Smith & Butler to renovate their entire home.

The extension plays an important part in the scheme, creating a large open-plan kitchen and dining space facing the rear garden.

With its Japanese-style appearance, the extension stands out from the brick walls of the main house, but neat proportions and a pitched roof help to tie old and new together.

Although it looks like there is a lot of blackened wood, in fact the only element is a large window seat built into the glazing. The facade steps to help this element fit it, while the steel-framed windows are finished in black to match.

Schiller, like an increasing number of Western architects and designers these days, created the house’s arresting exterior using a process known as Yakisugi, a ­centuries-old Japanese ­technique for preserving and finishing wood by charring it with fire. The treatment — which leaves behind a dense, carbonized layer of blackness — has been around since at least the 18th century, though earlier examples exist. It began as a practical process used mostly for fencing and the facades of rural homes and storehouses, which held valuables, like rice, that families hoped to protect from blazes. Interestingly, while it is no longer as popular as it once was in Japan, it’s found new life in the West. ‘‘It’s become quite stylish,’’ says Marc Keane, a landscape architect and author who has lived and worked in Kyoto for 18 years, ‘‘but in the past, in Japan, it was considered countrified.’’

Yakisugi is the Westernized term for what is known in Japan as yaki sugi-ita (or just yakisugi), which translates loosely into ‘‘burned cedar board.’’ (Although in English ‘‘sugi’’ is colloquially defined as cedar, it’s actually Cryptomeria japonica, a Cypress-family species indigenous to Japan.) To achieve the effect, planks of wood are treated with heat on their outward faces only: Traditionally, three boards are tied together lengthwise to form a triangular tunnel. The interior is then set on fire and the scorched surface cooled with water.