Our homes and buildings in the future could be made out of fungi, and this new method may be significantly more sustainable than any current building materials we use today. This form of bioconstruction repurposes a naturally occurring, rapidly renewing resource into a functional and sustainable building material that can reduce the environmental impact of our built environment.
Ecological impacts of the building industry
CO2 emissions for building operations reached their all-time high in 2019 and continue to rise as more structures are needed for our rising population. The emissions that come from the building construction industry account for almost 40% of total global energy-related CO2 emissions, according to a report from the International Energy Agency (IEA). Although we will continue to need more buildings for our growing world, the emissions from this industry are staggering and the cause for much concern. By 2060, the global building floor area is expected to double. Around 2.6 trillion square feet are expected to be added to the global building stock. That’s the equivalent of adding the floor space size of New York City every month for the next forty years!
The consequences of these building trends stretch far beyond carbon dioxide emissions. The built environment significantly impacts our natural ecosystems due to resource depletion, deforestation, and disruption of natural habitats. Constructing and maintaining buildings requires large quantities of raw materials such as concrete, wood, steel, and sand. These materials are often sourced through ecologically harmful processes. For instance, concrete, which is one of the most widely used building materials, is responsible for about 8% of the world’s CO2 emissions. Plus, concrete requires the extraction of raw materials like limestone and clay. These materials are almost always unethically sourced and lead to the destruction of natural habitats and the release of heavy metals and other pollutants into soil and water.
Another example is sand, which is in high demand for construction yet extracted at a high rate without proper regulations. As a result, aquatic ecosystems are damaged, and coastal erosion is increased. Excessive sand mining in river beds ruins the river’s natural structure, which can lead to riverbank collapse and groundwater depletion.
If building projects are expected to increase, we must explore and implement more sustainable alternatives to protect our planet from further damage. New homes and buildings will continue to be made, but at the rate they’re being built, our environment is expected to take a major toll unless some changes are made. In response to this crisis, architects and scientists have been working together to find solutions that are not only less harmful but also beneficial to our environment. One promising alternative lies in the humble fungal structures known as mycelium.
An organic solution to sustainable construction
Mycelium is a root-like structure of fungi that stretches for miles beneath the ground and trees, collecting water and nutrients from their surroundings. This unassuming part of fungal organisms is rapidly changing how we view sustainable building materials.
Mycelium’s use as a material has been explored for over a decade, but it has gained more attention in recent years and commercialized on a broader scale. One of the first pioneers of mycelium technology was Gavin McIntyre and Eben Bayer, the creators of Ecovative Design. They introduced sustainable mycelium packaging materials back in 2007.
Ecovative’s process starts by mixing fungal spores with a substrate made from organic agricultural waste byproducts like corn and cotton husks. This blend is placed into molds and left to develop a controlled environment. As the spores mature, they turn into mycelium, which consumes the organic waste in order to grow. After a few days, the mycelium forms a dense fibrous network that binds with the waste to form a solid structure. Once the mycelium growth reaches a certain stage, it undergoes heat treatment to sterilize it and avoid further mycelial development. The result – a lightweight yet durable material that mirrors the shape of the original mold.
The process of transforming mycelium into a usable product isn’t one size fits all. Different fungi and procedures are necessary depending on the final material it’s being used to create. Mycelium’s uses and applications go far beyond biodegradable packaging. It has been used to make food products such as plant-based meat substitutes as well as textiles to replace plastic-based fabrics or leather. Mycelium can also replace products traditionally made from styrofoam or fiberglass, such as surfboards and bicycle helmets. Moreover, mycelium stands out as an excellent choice for building materials.
The perfect sustainable building material
One crucial feature of mycelium is its ability to absorb sound. It can significantly reduce external noise, making it a great choice for buildings situated in noisy environments.
Additionally, mycelium performs exceptionally well as an insulating material. It keeps buildings warm in cold months and cools during the warm ones. This contributes to the sustainability of the building by reducing the need for energy-consuming artificial temperature control systems. Some types of mycelium materials are also fire resistant, giving a safety advantage compared to certain traditional construction materials.
Furthermore, some mycelium mixes are comparable to wood in terms of hardness and can be incredibly dense. Since mycelium can take the form of different molds, it can be made into various shapes and sizes required for a construction project.
Heat-cured mycelium is relatively water resistant, but since it is biodegradable, it will require a protective coating to protect it from outside elements and weather exposure.
How are structures built by mycelium?
Like other mycelium products, specially selected fungi and organic waste substrates are used to create the perfect building materials needed to construct a structure. Last month, research and design collaborative PLP Labs demonstrated a 100% bio-based installation during Clerkenwell Design Week in London. They wanted to illustrate how civilization and nature could form a positive symbiotic relationship through a process called symbiocene.
They used a 3D-printed mold made from wood fibers and bio-resin left over from sawmills. Specially selected mycelium was placed into these molds to create unique structures that can be used as modular building blocks. These blocks can be put together and taken apart easily, similar to how legos work. PLP Labs believes that “one of the aspects of future architecture is to make demountable buildings.” This form of modular construction lowers the amount of waste sent to landfills since off-site construction recycles and reuses excess materials for other projects. Plus, these buildings can be recycled, and their components repurposed into new buildings instead of demolishing and discarding them. Modular buildings are also constructed significantly faster than traditional methods while preventing the daily transport of materials to and from the construction site each day.
This method of creating mycelium modular construction blocks is being implemented by several architectural companies and may hit the mainstream construction industry within the next few years.
Mycelium’s future in sustainable building
Rob Bakker, the co-founder of PLP labs, tells Wired, “Mycelium has so much quality that we normally look for in materials that are mined, made out of mineral rocks or made out of fossil fuel, all the foams we know. Most of these have a big penalty to the environment. And mycelium does not.”
Mycelium’s practical qualities and sustainable cultivation process make it a potential game-changer for construction. As Baker points out, whether mined or synthesized, traditional materials can carry a significant environmental penalty. If we replace many of these materials with mycelium-based methods, there’s a chance we could hit net zero construction emissions by 2060. As a result, we can continue to meet our increasing need for infrastructure and living spaces without further stripping the planet of its finite resources, destroying ecosystems, and adding harmful carbon emissions to our atmosphere.