Thomas Robinson, founder of Lever Architecture, is widely hailed as a pioneer in designing tall buildings made of wood instead of concrete.
The all-wood building that houses Robinson’s office is only four storeys, but it’s a forerunner to Framework, a 12-storey tower scheduled for construction in the Pearl District in Portland. Once completed, it will be America’s tallest human-occupied structure made entirely from wood.
Although wood has been used in buildings for millennia, it is currently experiencing an architectural renaissance. Tall wood buildings have been constructed in the UK, Finland, and Sweden, and a 24-storey structure is currently being built in Vienna. A 35-storey Paris tower has even been proposed by a Canadian firm with a strong background in wooden structures.
Although U.S, building codes generally prohibit wooden buildings more than 85 feet in height, the federal government has initiated research into constructing with wood in an attempt to energise the country’s timber industry.
These new skyscrapers are not made from traditional wood planks, however. Instead, they use mass timber, an innovative wood product. Framework’s structure will be made from glue-laminated timber while the walls and floors were be cross-laminated timber panels.
Robinson and his team subjected both timber types to strict fire testing. After being placed in a furnace and weighed down for two hours, a joined beam, column, and cross-laminated timber panel were charred but structurally intact, Mass timber does not catch fire easily, and the charred outer layer that appears when the substance is burned actually insulates the wood.