“When we look around us at cement and concrete, it can be easy to forget that cement is the second most-used material on earth after water. Its impact is huge,” says Chelsea Heveran, an assistant professor at Montana State University. One report by the Chatham House shows about 8% of global carbon dioxide emissions each year comes from cement production. Finding a sustainable substitute for cement and bricks could significantly reduce the environmental impact of the construction industry.
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By 2030, the global volume of construction output could grow by 85% or $15.5 trillion. (Bold Business)
Construction projects account for 25% to 40% of the world’s total carbon emissions. (US Green Building Council)
The global buildings sector consumes around 36 percent of the world’s energy. (Bold Business)
According to thedenverchannel.com, Heveran and her colleagues are working to find more sustainable ways to replace cement and concrete — and fungi seems to be at the center of some of the most promising technologies. The bacteria are small and grow quickly. When mixed with wood chips in a process called biomineralization (think seashells, bones, geographic formations) they can form a strong bond. The new material has already been used to stabilize soil and patch leaks in oil and gas lines.
The folks at Montana State are not alone in their fungi experiments. The Wall Street Journal published an interview with an MIT research team that has developed bricks from sawdust and fungi. The fungus digests key plant proteins to produce chitin, which is the main ingredient in exoskeletons of creatures such as beetles, shrimp, and lobsters. Chitin is a strong but flexible material, which makes it appropriate for multiple building applications.
The type of mushroom (i.e., fungus) and plant protein that is used can change the quality of the end product. Researchers have developed everything from a very foamy material that can be used as an insulation or a packaging Styrofoam-type replacement, to a very strong substance that can be used for bricks. The brick material needs to be compressed and then dehydrated in a baking appliance, but at the end of that process, you end up with blocks that beat traditional building materials on several key metrics, among the most important is strength. Mushroom blocks can withstand greater impacts than traditional bricks, as well as be lateral loading to resist earthquakes without having to use steel reinforcement girders. Add in being relatively lightweight, fire retardant, insulative and biodegradable — and you have a product that merits a second look.