The Province carefully considers a number of factors and perspectives before making any substantial changes to the BC Building Code, balancing safety, cost and social benefits to arrive at the best policies and standards for British Columbia. Consultant reports were one element used in the development process for the mid-rise wood-frame residential construction code changes. The following reports provided an opportunity for the Province to determine the most appropriate way to raise the height of wood-frame residential buildings in B.C.
As part of this work, some suggestions were put forward that merit further review, but were not central to raising the ceiling on wood-frame construction. These recommendations will be given further consideration when the Province next reviews the BC Building Code.
Other major steps in this development process included:
As well, stakeholder feedback from technical advisory groups, online consultation and direct contact with the project team helped to shape the code changes approved in early January 2009.
GHL Stage 3 Report - Technical and Process Risks in 5 and 6 Storey Wood-Frame Buildings of Residential Occupancy
In this report, GHL Consultants Ltd. summarizes and updates their work in the previous two stages as well as provides areas for future consideration. The recommendations for future work include: building requirements for an aging population, construction fire safety, reviewing building height and area limitations, and assessing whether the reliability of sprinklers are underestimated. The Province has identified some of these for future code work, while others have been referred to the national code change committee because they have implications outside of British Columbia. Overall, the report concludes that:
Senez Reed Calder - Review of the Proposed Building Code Changes to Permit 5/6 Storey Wood-Frame Construction
In this report, Senez Reed Calder Forensic Engineering Ltd. (SRC) provides a peer review of GHL's proposed code change recommendations to the Province of BC. The intent of this report was to obtain another point of view to assist in drafting code change language for the online public review. The report:
GHL Stage 2 Report - Recommended Building Code Changes to permit 5 and 6 Storey Wood-Frame Buildings of Residential Occupancy
In this report, GHL Consultants Ltd. recommends code changes for the Province of BC to consider. These recommendations helped to inform the code change language tested during the online public review. All of the consultant's technical recommendations were carefully considered. Some technical recommendations were not included because they did not effectively balance cost and life safety outcomes. For example, the consultant's recommendation to require two layers of gypsum in exit fire separations to address the risk of improper installation was not adopted because the code uses performance standards and already requires the exit fire separation to have a one-hour fire rating. Other examples require further risk analysis to ensure that safety is not being compromised, such as the consultant's recommendation on horizontal exits, which could reduce the cost of construction. And finally, some recommendations were partly adopted, such as non-combustible exterior cladding where the reference to vinyl over gypsum being acceptable was removed because the code already allows vinyl over gypsum if it meets the fire performance standard.
In addition to the issues addressed in the recent code changes, the report provides some recommendations for code changes that will be subject to future consideration. These include:
GHL Stage 1 Report - Building Code Provisions for Residential Buildings and Identification of Technical and Process Risks
This report from GHL Consultants Ltd. examines the technical and process risks associated with six storey wood-frame buildings. The primary focus is on fire safety, seismic, structural, wood-shrinkage and building envelope. This initial risk assessment concludes that there would be little or no increase in technical risks allowing higher wood-frame buildings provided certain types of changes were made to the building code to account for the configuration of higher wood buildings. The majority of process risks identified in this report relate to issues not specific to this project but to broader construction industry issues.
Senez Reed Calder Historical Report
This report responds to three questions about the basis and development of the height and area requirements for combustible residential construction in the current edition of the British Columbia Building Code (2006 Edition). The report concludes that, while building code limitations on the use of combustible building materials have evolved over time, the fire protection requirements in the national building code are still based on fire fighting abilities from 100 years ago.
Scoping Review - Multi-level wood-framed structures: requirements for building beyond four storeys
This scoping review was an inter-jurisdictional scan, conducted by the Province of BC, to identify other mid-rise wood-frame projects and key considerations and issues. This work helped us to develop a work plan for further technical and policy analysis. Both the full report and an executive summary are available.
