Traditionally, mid-rise buildings, typically 6-12 stories in height, have used concrete and steel as
structural materials. Recent advancements in engineered wood products, as well as increased concerns for environmental impacts, such as carbon emissions, are driving interest in utilizing mass timber as the primary structural system for mid-rise buildings, particularly residential projects in British Columbia. Demonstration projects like UBC Brock Commons Tallwood Building have showcased the feasibility and opportunities of mass timber structural systems, and anticipated changes to the national and provincial building codes could facilitate the development of mass timber buildings up to twelve stories in the near future.
The City of Vancouver is the regulating body for the building construction in Vancouver and as such, is developing policies that could incorporate considerations for building mid-rise mass timber buildings. While there has been a significant amount of well-documented research on the characteristics and performance of mass timber products and structural systems, there has been less on the cost implications and affordability factors of mass timber buildings above six stories. Cost is a major driver and constraint for decisions at every stage of building projects, from planning through operations, and the lack of information is an area of uncertainty in the widespread adoption of mass timber as a primary building construction material.
This study, Literature review of cost information on mid-rise, mass-timber building projects, was initiated by the City of Vancouver’s Sustainability Department, and was undertaken in the summer of 2019 by the University of British Columbia’s Sustainability Initiative. The study aims to develop an understanding of various cost indicators and the data available in the literature to identify evidential support for the benefits of mass timber construction. The results may inform the City of Vancouver on the current trends, knowledge gaps and future research identified in the literature, and serve as a starting point in collecting cost relevant information for policy and regulations.
The Tallwood House project was intended to advance the design and
manufacture of mass timber products in Canada and demonstrate
that mass timber is a viable structural option for mid-rise and
high-rise buildings. The use of mass timber and engineered wood
products in high-rise construction is becoming more common
around the world leading to a growing interest in the performance of
mass timber over time.
This report describes the performance of the mass timber structure
in Tallwood House, between September 2017 and August 2019,
based on measurements of the moisture content in the prefabricated
CLT floor panels and the displacement of the vertical structural
system. It is intended to initiate discussions on the performance of
mass timber structure elements during building occupancy and lead
to further research that can explore the influential factors.