Residential Mid-Rise Wood-Frame Code Change
In May of 2008, Minister Rich Coleman announced government's intention to increase the maximum height for wood-frame residential construction from four to six storeys. These new BC Building Code requirements were approved in January 2009 and become effective April 6, 2009 giving the residential construction sector time to prepare for implementation.
Process
The development process for this change involved work in a number of areas to ensure that proposals to change the code received a high level of scrutiny and due diligence. This included:
- A scoping review to indentify potential risks and explore how mid-rise wood construction has been regulated in other jurisdictions;
- Contracting expert consultants to further clarify technical and process risks and recommend Code language to mitigate them;
- Conducting or supporting research in key risks areas such as seismic performance of mid-rise wood buildings and an historical perspective on how fire risks are managed in the Building Code. In July 2009, a full-scale mid-rise wood-frame building built with BC wood was successfully tested on the biggest shake table in the world in Miki, Japan.
- Working with leading experts and a wide variety of stakeholders in technical advisory groups to develop code change proposals;
- An online public consultation to solicit public and stakeholder feedback on code change proposals. The feedback received from building industry stakeholders, local governments and the general public were considered in finalizing the changes to the new code requirements. A clear majority of consultation respondents supported the proposed changes and several adjustments were made to the original proposals in response to feedback. The exterior cladding proposal was altered to clarify the performance basis of fire resistance requirements, the shear wall integrity proposal was adjusted and the yielding diaphragm proposal was withdrawn.
- Ongoing work with the residential building sector and local governments to help provide guidance as we implement this building form in BC.
- A Technical and Practice Bulletin on Structural, Fire Protection and Building Envelope design for mid-rise wood frame buildings is now available. The bulletin was prepared by the Association of Professional Engineers & Geoscientists BC (APEGBC) with the financial support of the Building and Safety Standards Branch.
Click here to link to the Technical and Practice Bulletin.
The scope of this project is focused on code changes specifically to allow an increase in the height of wood frame buildings from four storeys to six. During this process, we received a number of useful suggestions for general improvements to how construction is regulated, which will help inform future code development.
Concerns related to fires in wood buildings under construction were discussed extensively during the process. The Building and Safety Standards Branch is continuing to work with the Office of the Fire Commissioner and building sector stakeholders on strategies to reduce these risks.
More Information
View the Code Change Development Plan to find out more about how this process contributed to the development of the code changes for mid-rise wood-frame construction here.
View the new BC Building Code provisions here.
View research and consultant reports prepared for this code change process here.
