Standards · Design principles · Practical applications · Professional development · Decoding the NBCC Wind Commentary

Let’s be honest, NBCC Part 4 can be dense. When you get to wind loads in Section 4.1.7, it’s a flurry of equations, factors, and tables. You know the rules are in there, but what about the ‘why’? Why is the gust factor 2.0 for the main system but 2.5 for cladding? When do you really need to jump from the Static to the Dynamic Procedure?

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Standards · Design principles · Practical applications · Unpacking the Key Wind Design Changes in NBCC 2020

Another code cycle, another round of changes to get our heads around. Just when you think you’ve got your spreadsheets perfected, the new National Building Code of Canada (NBCC) lands on your desk. While the 2020 edition brought updates across the board, the wind load provisions in Subsection 4.1.7. have some particularly noteworthy changes that are already impacting our designs.

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Standards · The “Why” Behind NBCC’s Snow Load Factors

If you’re a structural engineer in Canada, you’ve stared at this equation more times than you can count:

$$S = I_s[S_s(C_b C_w C_s C_a) + S_r]$$

It’s the backbone of our snow load calculations, a formula we trust to keep our buildings standing through the harshest Canadian winters. It’s important to remember this detailed formula is from NBCC Part 4; the approach for simpler structures is different, as we’ve covered in our guide to wind and snow loads in Part 4 vs. Part 9.

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Standards · Design principles · Practical applications · A Structural Engineer’s Guide to the Journey of Snow

Here we go again. The first heavy, wet snow of the season is plastering everything in sight, and you get that familiar call from an architect. “We’re looking at a large, flat roof on this new project. What kind of snow load do we need?”

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Standards · Design principles · Practical applications · 5 Live Load Nuances in the NBCC Commentary

We’ve all been there. It’s late, you’re deep into a design, and you’re staring at the National Building Code, wondering if you’ve caught every little detail. The NBCC is a dense document, and its companion, the Structural Commentaries, is packed with the “why” behind the rules. It’s in those commentaries that we find the nuances that can make or break a design, or at least save us a headache during a plan check.

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Practical applications · A Practical Guide to Seismic Flexible Retaining Wall Design

So, you’ve just been handed a project with a decently sized retaining wall, and it’s in a location with some seismic kick. Immediately, you know that your standard static analysis isn’t going to cut it. The response of a retaining wall to seismic loading is a complex soil-structure interaction problem, and figuring out the right approach can be daunting. This is a classic example of where we move beyond simplified prescriptive rules and into the world of engineered precision using Part 4 principles.

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