Recently, Vancouver architect, Michael Green, issued a report entitled Tall Wood, arguing that skyscrapers and other tall buildings should use more wood as a primary construction material. His argument is that wood is up to the task, is less polluting, and is more environmentally sustainable than the materials currently used. Green’s (2012) buildings would employ “massive timber” elements such as cross laminated timber, laminated strand lumber, and laminated veneer lumber. Green is not suggesting that these tall building be of wood only. Rather, he is arguing that mass timber be integrated with other commonly-used structural materials such as concrete and steel.
While wood and wood-mix skyscrapers capture the imagination, extending the height of buildings with the more typical lighter-frame construction is perhaps a more practical concern. Currently, light frame construction tends to be limited to buildings of four storeys and less in North America. In some jurisdictions, this limit is mandated by building codes: in others, it is simply practice. Yet, the ability to construct acceptably safe timber structures with appropriate sprinkler and other technologies led Switzerland to change its fire codes in 2005 and allow the use of structural timber in medium-rise residential buildings of up to six storeys (Frangi and Fontana, 2010). Depending upon the application, mid-sized wood frame buildings can be a less expensive and more flexible alternative to other structures.
Despite the prevalence of wood frame structures throughout North America and parts of Europe, major concerns remain over the fire safety of such structures. This paper discusses some of the issues relating to wood structures and flammability.