Provincial and territorial governments in Canada are getting ready to release their updated building codes. They will almost certainly contain heightened seismic design requirements. Here is what’s changing and how you can get ahead of the codes.
In early 2022, the National Building Code (NBC) 2020 was released. While it currently only impacts federal projects, it is expected that provinces and territories will adopt the national model, largely unchanged, to create greater coherence and cohesion in buildings across the country. British Columbia (BC) has just released the 2024 code which will come into effect in March 2024.
The NBC 2020 includes several changes, including an update to seismic design requirements. There are two aspects that designers, developers and owners should be aware of:
- Current ‘seismicity’ requirements for design have increased. This means you need to start designing for higher seismic hazard levels. Design requirements vary across the country depending on location and soil conditions at that location—Southwest BC and the Greater Victoria region will see the greatest increase in design load requirements.
- New provisions have been included for lower-level earthquakes. These set performance requirements for certain types of buildings. Hospitals and schools are likely to be impacted the most (again, particularly in high seismic hazard areas like Southwest BC).
“The goal is for certain types of buildings like schools and hospitals to be able to withstand a lower-level earthquake without the need to repair the structural components after an event,” noted John Sherstobitoff, our Principal Seismic Engineer and Chair of the Task Group within the Standing Committee on Earthquake Design (SC-ED) that prepared these provisions for NBC 2020. “It’s based on the most current science and aims to raise the bar for a higher level of performance in certain buildings in the high seismic hazard areas of Canada.”
Get proactive
Once the provinces and territories publish their building codes, the new rules will come into effect. They won’t be retroactive, so existing buildings won’t need to make any changes. Projects permitted prior to the publication of the new building codes also won’t be required to meet the provisions in the new code.
This doesn’t mean that rushing out and getting your designs approved ahead of the code is the right course of action. Quite the opposite. Those buildings that don’t ‘need’ to meet the NBC 2020 requirements may fall behind in demand as newer, safer buildings built to the most current code become available. The smart move is to start designing to the new NBC 2020 codes now—voluntarily.
There are two big reasons why you want to start incorporating the NBC 2020 seismic requirements into your design as soon as possible, especially if permitting is expected to occur in 2024.
The first is to provide yourself with options. There are several approaches—both conventional and innovative—that can be used to meet the requirements. Base isolation, an example of innovative design, will enable new hospitals and schools to automatically meet these new provisions. Similarly, the use of supplemental energy dissipation devices (dampers), another example of innovative design, in this group of buildings will also automatically meet these provisions. Refined conventional design will also meet these provisions. These are options to consider early in the design process.
The second is cost. Incorporating the new requirements at the start of the design process is not difficult. Adding them or adjusting the design for them in the middle or at the end adds cost, delays project schedules and increases overall complexity. Technologies like base isolation and supplemental energy dissipation are most cost-effective when considered from the earliest portion of the design process.
“It’s not just about meeting the new regulations. It’s about being able to get your building back up and running as quickly as possible after a moderate to large earthquake, with no need to worry about structural integrity or damage. It’s about improved resilience, risk management and enhanced business continuity,” adds John Sherstobitoff.
There is an alternative
Another interesting and underappreciated aspect of design versus code is the allowance for what’s called ‘Alternative Solution’ for building design. One can consider a performance-based design and have it peer reviewed. If it meets the objectives of the code, it may be accepted by Authorities Having Jurisdiction in lieu of a code-based design.
In some cases, performance-based design could save significant costs across the overall project. But the trade-off is that you need to go through some rigorous analyses and reviews at the front end of the projects, and it may take more time to design, thereby impacting the project schedule.
It’s worth noting that there is already some discussion about whether performance-based design might become part of NBC by 2030 or 2035. This requires the authorities to codify the design methodology and performance metrics they expect designs to meet.
We can help
Our advice is to start thinking early about how the NBC 2020 might impact your designs and projects. If you have any questions, contact us.
With John leading our seismic engineering team, we have a top expert on hand who led the writing of the base isolation and supplemental energy dissipation provisions as well as the new lower-level earthquake provisions. John was also chair of SC-ED which prepared all the earthquake design revisions for the NBC 2015 and the NBC 2020.
John’s team is well-versed in base isolation and supplemental energy dissipation analyses and design. They were the engineers responsible for Canada’s first base isolation project and are currently working on the country’s largest base isolation project. They have also completed many supplemental energy dissipation projects and are now involved in a very large project in BC to incorporate supplemental energy dissipation devices.
To find out how we can help you implement the new requirements of NBC 2020, and designs involving base isolation and supplemental energy dissipation, contact John Sherstobitoff.