The use of wood is limited in larger and taller buildings by the National Building Code of Canada (NBCC) based on concern of increased fire risk. The current requirements were developed long ago, under much different conditions than today. Since then the industry’s knowledge of fire science has evolved considerably, fire service equipment and capabilities have improved, detection and suppression systems have advanced, construction materials and techniques have changed significantly, and public awareness and education regarding fire safety has increased.

Having an understanding of the knowledge, capability, materials and methods used to develop the height and area limits and the risks they were intended to mitigate, sets the basis for re-examination of those limits in a current context. This can be achieved through a historical examination of the development of the limits and their bearing on the use of combustible construction in buildings.