Is Wood a Good Building Material for Skyscrapers?

The Japanese company Sumitomo Forestry is planning to build a 70-story tower in Tokyo that is made almost entirely of wood -- although it won't be completed for more than 20 years. An elaborate steel framework will protect the 1,148-foot (350-m) building from Japan’s regular volley of earthquakes, but 90 percent of the W350 tower will consist of cross-laminated timber (CLT), a building material designed to be fire resistant and more structurally stable than steel when subjected to high temperatures. The cost of building W350 is expected to be nearly twice the cost of a conventional skyscraper.

Harvesting tomorrow's skyscrapers:

• The Japanese government is encouraging developers to use more wood. A law enacted in 2010 requires government buildings up to three stories high to be constructed with wood.
• Concrete and steel buildings are thought to be responsible for a carbon footprint of as much as 8 percent of all global carbon emissions. Wood, on the other hand, stores carbon instead of sending it into the atmosphere.
• Canada currently holds the record for the world's tallest timber tower at 164 feet (50 m) tall. The 18-story student residence at the University of British Columbia has been called the world's tallest "plyscraper."