Will we ever be free from concrete?
Did you know that the cement industry plays a significant role in contributing to global carbon dioxide emissions, way more than flying or shipping?
Though the material is the foundation of modern development, more than four billion tons of cement are produced every year to build houses, motorways, and flood defenses - and now they are responsible for about eight percent of global carbon dioxide emissions.
After water, concrete is the most widely used substance on Earth. Reinforced concrete was introduced in France, in the mid-19th century. Since then, it has been used to build pretty much all buildings. It is quite impossible to think of a future without concrete.
But one can't deny its role in increasing carbon dioxide emissions, and the clock is ticking. It is high time we seek alternatives for the building blocks of our metropolises.
Fret not, we do have options. Made of waste steel dust and silica obtained from the ground-up glass, ferrock is a top contender. The material was an accidental discovery by David Stone to keep iron from rusting and hardening up. Ferrock is incredibly hard - five times stronger than Portland cement, and yet flexible. It lowers carbon dioxide by absorbing and binding the gas as it dries, resulting in a carbon-negative process that can trap greenhouse gases.
Another material, ashcrete, made from waste fly ash generated in coal-burning operations, is like ferrock. Ashcrete is environmentally feasible, as 93 percent of the resulting substance is recycled material. Now, fly ash is produced by burning coal, which produces carbon dioxide. Nevertheless, the amount of carbon dioxide emitted for one ton of fly ash would still be significantly less than that produced during the manufacture of one ton of cement.
Next is a biocomposite material, hempcrete, suited for most climates. It weighs only about an eighth of regular concrete weight and lacks the brittleness of concrete. The lightweight properties of the material make it easy to transport.
A surprising alternative in this race is mycelium, thin root-like fibers from fungi that grow underground. Mycelium can be used as a water, mold, and fire-resistant building material once dried.
Lastly, we have finite, made from desert sand. Now, while desert sand has been considered useless as building blocks, scientists from Imperial College London believe that finite can outperform concrete.
As evident, we have a plethora of options to construct our buildings in the future. The real question is if we can make the switch before it is too late.