Innovative architect David Benjamin walked into the offices of
Arup, a structural engineering firm to discuss the possibility of using mushroom bricks. Although a strange idea at first, this technology will benefit the architects of the future in propagating sustainable resources.
The construction industry is dependent on fossil fuels leading to a big carbon footprint and large costs. It is no surprise that the construction and building industry wants to move toward a greener more sustainable future.
Mr Benjamin’s brick is made largely of mushroom mycelium, grown on agricultural waste, produced by a company call Ecovative.
“Structural engineers work with architects a lot; quite often we see completely crazy ideas,” Matthew Clark told the American society of mechanical engineers (
ASME).
“But this was probably one of the most crazy.”
Sustainability and Recyclability
According to ASME, structural engineers generally build things of tried and true materials, largely concrete and steel, whose properties are well known."This is a hybrid of what I call an ancient technology of mushrooms and a totally new technology of computation and engineering, “Mr Bejamin told the BBC.
The mushroom - or mycelium, the vegetative part of the fungus - is an ideal material, Mr Benjamin said.
These bricks score high marks for sustainability because they were "grown" with no carbon emissions and no waste.
According to Ecovative, it is also affordable, fire resistant and has low or no VOCs. In addition to naturally-grown insulation, the house also has ceiling tiles made of mushroom material.
“At its core, our vision in the building industry is to offer architects, builders and consumers the ultimate solution for eco-friendly, energy-efficient construction at a price that is far less costly to our health, the environment and our pocketbooks,” Ecovative Co-Founder Eben Bayer told Inhabitat.
The design
According to ASME, making the bricks is simple enough. Mix some mushroom spores with farm waste, pot it, and let it grow. Then take the bricks out of the molds and bake to kill the mushrooms. The process gave the Arup team essentially two variables: the type of agricultural waste used and the time that the mushrooms were allowed to grow.
They tested six iterations with load tests at Columbia University, wind tests at BMT Fluid Mechanics, and aging tests at Advanced Metal Coatings. For maximum stiffness they settled on corn stalks for waste material and a 10-day growth period.
The final result is a mushroom brick that’s 200,000 times softer than steel, 10,000 times less stiff than a typical housing brick, but capable of holding the equivalent of 50 cars.
According to the BBC, the mushroom brick is "grown" by mixing together chopped-up cornhusks with mycelium.
The mixture is then put into a brick mould and left to grow for five days. The result is a brick that is solid, but lightweight.
This method lets builders use local materials like agricultural waste, and also makes the bricks biodegradable.
Weatherproof?
The idea of a durable but biodegradable brick is something of an oxymoron. Weather-proofing them without destroying their essential compostability was a conflict from the start. Sealing each brick in polyurethane would have solved the problem completely but would have flown in the face of the concept as well as the rules. Instead, they used natural oil penetrated into the bricks.
They tested the coated bricks in a “domestic shower,” says Mr Clark, and found they only gained a few percentage points of mass. “They don’t go really soggy and flexible,” he says.
Those few percentage points would mean the structure would degrade over time, part of Benjamin ’s initial conception.
In its first few weeks of existence the tower was hit with heavy rainstorms. “You can see the difference, but it’s held up pretty well,” Mr Clark told ASME.
“It can also withstand 65-mph wind gusts (the museum will just shut the courtyard if they get that high) as well as the weight of a few extra bodies. “We’ve seen people climb it—not advisable—but it’s a very robust structure.”
“As structural engineers we tend to be asked to design things that have to last for 50 years and at large scales,” says Mr Clark.
“While the mushroom brick is not directly applicable to that, it’s changed the way we think about materials in general. It’s also remarkable from an engineering front: You can still build with a material 200 times less stiff than masonry. You don’t have to immediately dismiss it because it’s soft and floppy.”
The future of mushroom materials
Mr Benjamin's belief in the power of biotechnology is evident in the name of his architectural firm, The Living.
"We want to use living systems as factories to grow new materials," he told the BBC. "Hopefully this will help us see cities more as living breathing organisms than solid, static, inert places."
Phil Ross, Chief Technology Officer of MycoWorks
has spent the last 20 years developing sustainable materials from mushrooms.
According to Quest, through a process he calls “mycotecture,” Mr Ross crafted furniture, interlocking blocks, and a small teahouse.
"It just seems like an inevitability that this is going to be a popular material," he said"This stuff can be used to replace a lot of engineered woods, a lot of plastics, a lot of materials that we can't even think of," said Mr Ross.
"It just seems like an inevitability that this is going to be a popular material."
Images via Ecovative
