A new housing complex in Paris was made from the rubble of a 1960s building.
Called Recygénie, the buildings are the first to use 100 percent recycled concrete. That's because, when a group of ageing apartment buildings from the 1960s were recently torn down outside the French capital, the demolition waste wasn’t thrown out - but put back to work in an innovative new process called Ecocycle.
The recycled material was mixed with recycled water and cement made from materials that included recycled sand, paper by-products, and steel slag. Nothing like this had ever been done before. “It took a year to convince our own cement experts to move to 100 percent recycled cement,” says Edelio Bermejo, who leads innovation and global R&D at Holcim, the giant Swiss building materials company that developed the process. Seqens, a French social housing development company, partnered with Holcim on the new project after learning about the new system.
French regulations allow for only a small percentage of recycled material in new buildings, so the team at Holcim had to demonstrate to the authorities that there was no compromise in quality with a shift to a fully recycled product. Last December, the recycled-concrete superstructure was completed, saving a whopping 6,000 tons of new material.
While (currently) essential to building the structures that improve our everyday life, concrete is responsible for 8 percent of global carbon emissions, so all such innovations like Holcim's are to be welcomed and applauded.
Residents will begin moving into the buildings later this year.