When most of us think of construction materials, we imagine things like metal, concrete and wood – maybe even the earthworks of ancient architecture if we cast our minds back far enough.
But Christopher Maurer of Redhouse Studio Architecture has a new material he believes might just have the potential to shape the future of the industry – and you’re more likely to find it in your fridge or as part of your favourite meal than on a construction site:
Built spoke to Maurer to learn about his revolutionary approach to using mushrooms in construction, from creating a more eco-friendly material through breaking down toxic construction waste to even providing a new way to approach urban development in emergent nations.
Why mushrooms and construction are a natural fit
Maurer said mushrooms have a structure that is easily modified to mimic human-created construction materials. ‘The root structure of mushrooms is called mycelium, and they’re basically these little strands that resemble the roots of plants. They branch between all of the different particles of the sawdust they grow in, binding them together the same way that glue would bind together sawdust in a medium-density fibreboard.’
This process of transforming sawdust or dead wood back into a usable material is essential to the mushroom’s natural function. ‘From their perspective, this is very similar to breaking down their food’, Maurer said. With a little help from Maurer and his team, mycelium can be made into a material that closely resembles wood. ‘When we heat and compact that, we can get material that’s just the original wood, and we can pretty much form it into any kind of shape we want’, Maurer explained.
Using mycelium to eliminate construction waste
But mushrooms don’t just make new material. Maurer said they can actually be the industry’s best ally in eliminating dangerous and toxic construction waste, using his Biocycler process. About ‘600 million tons of C&D [construction and demolition] waste goes to landfills every year’, Maurer said. ‘All of that basically just gets converted into greenhouse gases, and it escapes into the environment.’
Maurer and his team realised that the large amount of wood used in the demolition materials that were found all over his hometown of Cleveland meant that the fungi would have something to feed off of as they grew, effectively remediating dangerous chemicals from the built environment.
‘There are two ways that the fungi can eliminate construction pollution’, Maurer said. ‘With the petrochemicals, the enzymatic release of the fungi actually breaks them down into smaller safer molecule chains. But when it comes to things like heavy metals, what you have to do is exactly the opposite, binding them with larger molecules, which makes them non-biologically available.’
Both of these processes mean that any toxins from abandoned construction sites are rendered safe when broken down by mushrooms, making them harmless if inadvertently consumed; they also prevent them from leaching into the soil or groundwater if materials end up in a landfill.
How mushrooms might shape the developing world
While Maurer’s work in Cleveland focuses on breaking down abandoned structures and reducing the city’s high rates of childhood exposure to construction contaminants, he’s used a similar approach in Africa to create materials that provide a solution to food scarcity as they create more eco-friendly, sustainable structures.
‘I’ve spent a lot of time working in the developing world and learning how to make do with limited resources’, Maurer said. ‘I knew that food security was an issue, as was environmentally sound and limited resource building. I wondered about putting those two things together and came up with a concept for refugee shelters, where you would actually make food and building materials at the same time. The folks that would work on doing both of those things would have jobs and economic opportunities throughout the process.’
Working with Standard Bank, Africa’s largest bank, Maurer and his team have started a project founded on that idea, which also works to reduce the impact of an invasive species. ‘In Namibia there’s a problem with the encroacher bush, which is spreading rampant throughout the country and leading toward desertification’, Maurer said. ‘What we’ve discovered is that it makes great fodder for growing edible mushrooms. We’ve set up a farm where we take that substrate and we throw mushrooms on it. The mushrooms are harvested and they go to market, and they’re used to feed people and generate incomes. Then the waste material is used for making building materials.’
A more eco-friendly material
As research into mushrooms continues, Maurer said he believes they have the potential to become a valuable resource for eco-friendly jobsites.
‘We’re optimistic that it can replace many of the different building materials that are out there’, Maurer said. ‘What we’re making in Namibia is comparable to a concrete block. The compressive strength is slightly less than your average concrete block. But it’s produced food. It’s a circular resource. It’s using waste material, converting that into food, and it’s storing carbon dioxide. It’s doing all of these beneficial things, and the material actually stores carbon, so you have all these co-benefits of using that material. The trade-off between that and the concrete block starts to look really good.’
Once the technology advances to creating larger slabs of material, Maurer said mycelium blocks could actually be an even more environmentally conscious alternative to mass timber. “’You could build very quickly with it. But instead of using virgin lumber, you’d be using waste material and either remediating things through the Biocycler or creating food at the same time, food or medicinal products from the recycling of this waste biomass’, Maurer said.
As the ecological impact of the construction industry remains a concern, Maurer said he thinks the appeal of mycelium will grow. ‘Manufacturers and governments are looking for carbon-neutral or even carbon-sequestering material’, Maurer said. ‘These biomaterials are going to lead the way to a future that will be focused on net -zero carbon and things like that.’
These technologies are critical to helping the construction industry grow as sustainably as possible. ‘It needs to happen’, Maurer said. “’We’re looking at a scenario where we would double the footprint of all the buildings on the planet by 2060. If we continue to build with current methods, we’ll only exacerbate the climate scenario that’s wreaking havoc on the planet right now. Something’s got to give.’ Can mushrooms offer one of the vital solutions?