Some scientists speculate that concrete production contributes to 6% of the world’s greenhouse gasses. Switzerland intends to improve those numbers with revolutionary concrete creation techniques.
Twenty years ago, Zurich began a concrete recycling program. As a result, the country’s largest city leads the way in sustainable construction. For example, in 2002, Zurich builders constructed a school; 80% of concrete used came from recycled material. Builders pushed even further in 2013 by using CO2-reduced cement.
Concrete emits greenhouse gasses because calcinated limestone must reach 2,642 degrees Fahrenheit during production. The Swiss cement industry circumvents this by using calcined clay, slag, and fly ash. The use of these materials lowers the needed temperatures to make concrete.
Swiss manufacturers define recycled concrete as material that uses at least 25% demolition waste. As of 2019, Swiss authorities estimate that use of recycled material saves 17,000 cubic meters of virgin materials and landfill space per public building.
Switzerland offers new and exciting techniques that builders worldwide might consider as part of their green construction efforts regarding greenhouse gas emissions from concrete production.