Many plastic-based building materials that could be recycled aren’t, because most companies haven’t yet figured out how. The AZEK Company cracked this code, and diverted nearly 300 million pounds of waste from landfills in 2019. Every time an office building or an old home is demolished, all of the broken-down materials have to go somewhere. The US Environmental Protection Agency estimates that 230 million to 530 million tons of construction waste are produced annually — and much of that material ends up in landfills. The bulk of construction and demolition waste is old bricks, masonry, concrete, wood and metal; but it’s not exclusively that. Some plastic-based building materials — such as windows, flooring and decking — that could be recycled aren’t, because companies haven’t yet figured out how to collect and reuse the plastic at the heart of these products.