Would you trust a mushroom?
World leaders have promised to end poverty, reduce inequalities, and tackle climate change by 2030 as part of the Sustainable Development Goals (SDGs). So how can we help? Buildings and how we design, construct, and live in them are an important factor in lowering the negative impact on our environment. Therefore, it is important to consider the methods and materials used in construction. Turning to nature for sustainable building materials seems only logical. One material has been around for millions of years, mushrooms. But the question is, would you trust walls made of mushrooms?
If you are wondering how a mushroom can be strong enough to be used as a material product, you should know it is not just the mushroom itself. The major role of fungi in nature is to act as a decomposer. They grow on dead organic matter, disassembling and recycling back into the environment. Products are made from the roots of the fungus called mycelia. Mycelium is the vegetative tissue of fungus, through which it absorbs nutrients. It is a thread like network below the ground that connects to the visible part of the mushrooms above. Simply said, mycelium is combined with agricultural waste and, as they fuse, can be shaped into solid bricks. Over decades of research and development, scientists are narrowing in on technologies which allow engineers to use fungus as the main building material in construction.
In 2014, the architectural team, the Living, designed and installed the world's first mushroom brick tower named Hy-Fi in the courtyard of MoMA’s PS1 space in Long Island City, NY. The team constructed the organic, biodegradable bricks entirely from fibrous fungi agricultural waste. The fungus was grown to fit a brick-shaped mold in order to create a structurally sound, 40-foot tower consisting of 10,000 bricks that reaches 40-feet in the air.
Hy-Fi was the first large scale structure to use this mushroom brick technology based on a technique developed by Ecovative Design, who is manufacturing a wide variety of building materials made out of mushrooms, such as constructed bricks, insulation, and beams, that are as strong as wood. The bricks can be grown in five days and are stacked to create a structure of three merging cylinders. The top layers of the ‘bricks’ in the structure are used to grow the bricks below.
Renowned architect and MIT professor Carlo Ratti has grown a series of arched architectural structures from mushroom mycelium that are significant to the development of this biotechnology. His Circular Garden installation comprises of a chain of 60 four-meter-tall arches. End-to-end, the chain measures a kilometer which is a record length for the fungus material. “Nature is a much smarter architect than us,” said Ratti. “As we continue our collective quest for a more responsive ‘living’ architecture, we will increasingly blur the boundaries between the worlds of natural and artificial.”
There are both advantages and disadvantages to mushroom materials when comparing them to one of the most commonly used construction materials, concrete. On its own, concrete maintains a compressive strength of 4000 psi to 10,000 psi. Comparatively, the mushroom bricks can only withstand 30 psi. Though it cannot support as much weight, it is also much lighter than concrete. The mushroom brick weighs 43 kg/m³, while concrete weighs about 2,400 kg/m³. Despite the brick’s lack of compressive strength, its low density makes it useful in areas that do not need as much support. For example, it can be used as insulation and support for interior walls.
One of the most important disadvantages of mycelium is that its water resistance decreases over time, thus becoming vulnerable to mold and humidity. When dried out, the bricks can survive drastic weather changes from winter to summer without coating if it does not touch the ground. When in contact with the ground, a mycelium panel starts decomposing in about six weeks. On the contrary, if maintained in a favorable and stable condition, it can have a lifespan of 20 years. The biggest advantages of fungal mycelium are that it’s 100% biodegradable and can be found in abundance on the planet. The rapid growing tissue can expand under a wide range of environmental conditions. More specifically, the tissue can trap more heat than fiberglass insulation. It is fireproof, nontoxic, partly mold, and water resistant. When placing two alive, individual mycelium bricks together, the mycelium will rapidly spread amongst them; making a fast, easy, low-cost, and energy material production.
Mushrooms are one of many natural solutions that could replace conventional materials while being equally efficient, more ecologically responsible, and cost competitive. It is time to outgrow architecture made of inert materials and make architecture that grows itself.