"Reusing materials will be important for cities as they look to cut waste to meet environmental targets, and because rapid urbanisation will put pressure on the supply of materials such as cement and steel," writes Rich Heap. "I interpret large urban buildings to mean offices, housing developments, shopping centres, and industrial buildings. That's the easy part. The more difficult part is coming up with a single definition for recycling because there are three terms that are relevant to this discussion" -- recycling, upcycling, and downcycling.
"Waste from construction and demolition projects now accounts for 25 to 30 percent of total waste in the EU, and the proportion is similar in the US. This includes concrete, brick, cement, glass, wood, and metal. Much of this can be broken down and turned into new building aggregate."