Many big cities around the world are characterized by towering structures made of glass and metal. But soon another building material may be added to the list: wood.

  A recent innovation in the construction industry involves laminating wooden boards. The boards are then pressed together using industrial wood presses, which use pressure and steam to connect the boards. The result is called cross-laminated timber (CLT), an extremely thick plywood that is strong, durable and fire-resistant.

  With CLT, people can build larger wooden structures than before. These structures, called plyscrapers (a word formed by combining “plywood” and “skyscraper”) are popping up all over the world. Already Vancouver, Canada, has a 19-story plyscraper, and Vienna, Austria, and Milwaukee, USA, have 24-story and 25-story plyscrapers, respectively. Several plyscrapers top 60 meters, and one project in Norway is 85 meters high, making it the largest wooden tower in the world.

  Plyscrapers have the potential to be very good for the environment. The use of wood rather than traditional construction materials can drastically cut down on carbon emissions. When plyscrapers break down (as all buildings do), their materials can be recycled or broken down naturally, leaving little pollution behind.