Fungi could one day make up the walls of our homes — and include built-in climate control, researchers say | CBC News (2024)

David P. Ball · CBC News

· Posted: Jan 02, 2024 9:00 AM EST | Last Updated: January 2

A team of Vancouver academics is fusing the fields of microbiology and architecture to createliving building materials made out of oyster mushrooms and other edible fungi.

They say their research into "engineered living materials" could help curb the construction industry's high energy and environmental impact, replace traditional insulation, or even help regulate indoor temperatures as the climate warms.

One day it could even potentially help filter air pollutants such as wildfire smoke, according to a postdoctoral fellow at the University of B.C.

"This idea of engineered living materials, it's a very new concept," said Nicholas Lin, an engineer with expertise in microbiology.

"These materials are assembled by combining raw materials with living cells and exhibit some certain properties of living systems," explained Lin, whoseresearch straddles both UBC's microbiology and architecture schools.

His teammates at UBC's Biogenic Architecture Lab are creating various building materials filled with mycelium — the fuzzy-looking network of tiny, pale underground strands, or hyphae, that serve a functionsimilar to plants' roots.

But fungi, one of the oldest organisms on the planet at more than a billion years old, are neither plant nor animal.

The team of researchers mainly work with edible species, such as oyster, reishiand turkey tail mushrooms.

"Oyster is probably the most popular one because we know it's edible, there's no known toxicityand it grows very fast," Lin said.

'Dynamic, tunable'

One of his supervisors is associate architecture professor Joseph Dahmen.

Dahmen said his main inspiration over his years researching what he calls "mycelium biocomposites" was to reduce the energy and environmental impact of construction materials.

"The lion's share of the energy going into buildings is in the materials themselves," he told CBC News. "Mycelium biocompositesoffer a kind of biodegradable material to replace those."

To make the engineered living materials — whether bricks, gels that can take any shape, insulation, or drywall-like boards — he said the researchers mix mushroom spores with something high in cellulose, often a recycled or byproduct material such as sawdust, wheat chaff or rice husks.

While this has been done for years around the world with both fungi and bacteria, he explained, often the finished product is "cooked" to kill the organisms.

"We didn't invent the process," he said. "But what we're really interested in is the potential of these materials if they remain alive.

"So you could imagine a material that then becomes dynamic, tunable.We can make it different strengths. It goes on growing."

'Grows like mushrooms'

While Lin's PhD research had him killing microorganisms by creating antibacterial surfaces, now he's using 3D printers to help create a gel full of them.

"It's kind of similar actually, to kill something and to raise it," he mused. "Some parts of it arequite similar in the way you maintain a pure culture.

"But one thing that's always really interesting is — if we neglect the fungi, or if we forget to check up on it — sometimes it'll fruit a little oyster mushroom."

The speed oyster and other fungi can spread allows the researchers to test new ideas quickly.

And that's led the UBC lab to develop everything from a mushroom-based composting toilet tosolid sawdust bricks and benches.

"The expression 'grows like mushrooms' is actually accurate," Dahmen joked. "They're very fast growing, and they tend to be hydrophobic so they can repel water.

"We can match them to the unique environmental considerations for where we want to employ them."

Dahmen said at presenta whole house made of 3-D printed living mushrooms is purely hypothetical.

"I would say we're probably still a few years away from incorporation in mainstream buildings," he said. "But we're just starting to understand some of the potentials of these materials."

Built-in climate control

Lin said there are some even more complex functions the future may hold for living building materials — based on what he called the "environmental responsiveness" of fungi's hyphae.

A study published in the journal Proceedings of the National Academy of Sciences this year found mushrooms could lower their temperatureby an average of 3 C below their surroundings — which, Lin said, could point to climate control applications as the climate warms.

And with climate change worsening Canada's wildfire seasons, living materials filled with fungi might one day help clean the air in our homes.

"Could we engineer these mushrooms so if there's a lot of smoke from wildfires, they could recognize that — and produce more of these fibrous fuzzy materials to capture this particulate matter?"he speculated.

That's an idea that's still mostly science fiction, but Lin believes itrequiresfurther research.

"In the very, very far future, these biological tools might give us new ways and new insights to produce materials that are faster, better, cheaper — and in thelong term, more ecologically sound,"he said.

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