OBC 2024 Shingle Installation Requirements: Guidelines for Roofing Contractors in London, Ontario
Sarah's Expert Insight
OBC Compliance Specialist
"In high-wind regions like London or the exposed shorelines of Muskoka, strictly adhering to the fastener placement rules in OBC 9.26.7.4 is critical to prevent shingle uplift and premature roof failure. At empcontracting.ca Inc. your construction contractor in London, Ontario, we prioritize these low-slope and ridge standards to ensure long-term durability against Ontario's harsh freeze-thaw cycles and heavy snow loads."
Understanding Shingle Fastening and Installation under OBC 9.26.7
Properly securing asphalt shingles is fundamental to maintaining the structural integrity of a roof. According to the 2024 Building Code Compendium, specific fastening patterns are required to ensure durability against Ontario's varied climate.
Fastener Requirements and Placement (OBC 9.26.7.4)
For standard 1 m wide shingles, the code requires at least 4 nails or staples per shingle, ensuring no fasteners remain exposed. However, if using staples with an 11 mm crown, the requirement increases to at least 6 staples. These fasteners must be positioned 25 mm to 40 mm from each end, with the remainder equally spaced and located at least 12 mm above the tops of the shingle cutouts.
Securing Tabs, Hips, and Ridges (OBC 9.26.7.5 - 9.26.7.6)
To prevent wind uplift, shingle tabs must be secured using plastic cement (not exceeding 25 mm in diameter), interlocking devices, or self-sealing strips. When addressing hips and ridges, shingles must extend at least 100 mm on either side and maintain a lap of no less than 150 mm. Fasteners for these areas should be placed within 25 mm of the edge and 25 mm above the butt of the overlying shingle.
Special Requirements for Low-Slope Roofs (OBC 9.26.8)
Roofing projects with a slope of less than 1 in 3 (but not less than 1 in 6) require enhanced protection measures to mitigate water ingress.
Coverage and Starter Strips
For these low-slope applications, OBC 9.26.8.1 mandates that coverage must be no less than three thicknesses of shingle over the entire roof area. Furthermore, starter strips must be laid in a continuous band of cement at least 200 mm wide to ensure a watertight seal at the eaves.
For expert assistance with your next roofing or renovation project, trust empcontracting.ca Inc. your construction contractor in London, Ontario to provide code-compliant, high-quality results.
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.