2024 OBC Guide: Arch Roof Snow Load Requirements from empcontracting.ca Inc. in London, Ontario
Sarah's Expert Insight
OBC Compliance Specialist
"As a senior consultant at empcontracting.ca Inc., your construction contractor in London, Ontario, I've found that many designers overlook the specific downwind accumulation risks inherent in curved roof geometries. In snow-heavy regions like Muskoka or the wind-prone corridors of London and Oakville, strictly adhering to the 4.1.6.10 formulas is the only way to ensure the long-term structural integrity of modern arch-style buildings."
Navigating the 2024 Ontario Building Code (OBC) requires a deep understanding of structural load distributions. Section 4.1.6.10 specifically addresses the accumulation factors (Ca) for arch and curved roofs, which are critical for safe construction in the Ontario climate. If you are planning a unique structural project, empcontracting.ca Inc. your construction contractor in London, Ontario, is here to ensure your design meets every safety standard.
Understanding Snow Accumulation on Arch Roofs
For arch roofs with an edge slope (αe) of 30° or less, the OBC specifies that the accumulation factor is not uniform. The code distinguishes between the upwind and downwind sides of the peak to account for how wind moves snow across curved surfaces.
Key Calculation Requirements for Curved Structures
The accumulation factor (Ca) on the downwind side is determined by the ratio of the arch height (h) to the arch width (b). Depending on whether this ratio is between 0.05 and 0.12, or greater than 0.12, different mathematical formulas are applied to determine the horizontal distance (x) from the peak where snow will most likely settle.
- Upwind Side: Typically taken as 0, assuming wind clears the leading edge.
- Downwind Side: Requires specific Ca calculations based on the height-to-width ratio of the arch to prevent structural overloading.
Why Professional Compliance Matters
In regions like London, Oakville, and Muskoka, where snow loads can be significant, failing to account for these specific accumulation factors can lead to roof failure. empcontracting.ca Inc. your construction contractor in London, Ontario, specializes in translating these complex 2024 Building Code Compendium requirements into durable, safe, and compliant physical structures.
Disclaimer: This content is generated from the Ontario Building Code for educational purposes. Always consult with a licensed professional engineer or your local building department before starting any construction project in London, Ontario.