While living in Florida in early 2010, Dr. Gerhard Dust witnessed the devastation of the Haitian earthquake that left one and a half million people homeless. Without proper protective shelter, Dust realized, victims of natural disasters are at risk of perishing overnight.
“There are 1.2 billion people on this rich earth living under slum conditions or even have no shelter at all. Why is it so?” Dust asks. “It is because of the lack of available and affordable building material, and it’s the situation that currently building can only be done by skilled labor.”
Dust knew there had to be a better solution for building cheap, sustainable emergency shelters for displaced people, so he drew inspiration from a well-known children’s toy and the most abundant building material in the world: legos and sand.
In his talk at TEDxBinnenhof, Dust describes gathering help from friends, entrepreneurs and engineers to found PolyCare. Through the new company, Dust was able to invent an efficient system for recovery and reconstruction, enabling victims of natural disasters to build homes quickly – and with local resources. PolyCare’s primary material? Sand. A lot of it. But not just any kind of sand.
“All the buildings in Dubai, Abu Dhabi and Qatar are built with imported sand from the Philippines, Australia, and the Netherlands,” Dust explains. “That is because desert sand cannot be used for ordinary concrete.”
Coming up with a final product wasn’t easy. Because desert sand cannot bind with cement due to its rounded profile, Dust tried mixing simple sand with polyester resin in compact machines to create strong concrete. The final product was made up of 87% simple sand and 13% polyester resin, resulting in a compound three to five times harder than normal concrete.
If you’re having a hard time visualizing the process, Dust compares the machines to large kitchen appliances able to fit inside easily transportable containers. The machines mix the sand/resin compound and then feed it into a mold for shaping. The final product is a Lego-like block with the ability to harden in 20 minutes (regular concrete takes 28 days). Not only are the blocks fast-hardening, they’re reusable, and their familiar Lego shape makes them a highly intuitive building material. Dust claims that one machine can produce a house per day, and dreams that someday a refugee camp made of polymer concrete blocks will be transformed into a school or a hospital in the same community.
“Think of all the refugees moving from camp to camp or in slum conditions with no place to call home,” Dust says. “Empowering these people to build their own house will not give the chance to build their home, but their community and their future.”
For more, watch Dust’s whole talk below: