Cross-laminated timber (CLT) is a type of strong, lightweight wood that is made by stacking wood boards (called panels or lumber) in layers that are held together with glue. The layers are arranged so that the grain of the wood in each layer runs in a different direction, making CLT incredibly strong and stable. CLT is used to build houses, schools, offices, and other kinds of buildings. CLT is a great option because it is sustainable, environmentally friendly, and long-lasting.