Provincial code changes have been made to allow construction of light wood-frame buildings up to 6 storeys in order to satisfy the urban housing demand in western Canadian cities. It started in 2009 when the BC Building Code was amended to increase the height limit for wood-frame structures from four to six. Recently, provinces of Quebec, Ontario and Alberta followed suit. While wood-frame construction is limited to six storeys, some innovative wood-hybrid systems can go to greater heights. In this report, a feasibility study of timber-based hybrid buildings is described as carried out by The University of British Columbia (UBC) in collaboration with FPInnovations. This project, funded through BC Forestry Innovation Investment's (FII) Wood First Program, had an objective to develop design guidelines for a new steel–timber hybrid structural system that can be used as a part of the next generation "steel-timber hybrid structures" that is limited in scope to 20 storey office or residential buildings.
The results show that the presence of CLT infill walls significantly affects the systems overstrength value, by sacrificing ductility. From this research, it can be concluded that an overstrength factor of Ro = 1.5 and a ductility factor of Rd = 4 showed acceptable and economical design of the proposed hybrid structure.
