Ontario Building Code 2024: Wood Siding and Shingle Standards in London, Ontario
Sarah's Expert Insight
OBC Compliance Specialist
"Adhering to the precise overlap and fastening requirements in OBC 9.27.6 is the most effective way to prevent capillary action and rot in Ontario's humid climate. At empcontracting.ca Inc. your construction contractor in London, Ontario, we find that following these specific shingle grading and placement standards is particularly vital for projects in Muskoka and Oakville, where increased wind and moisture exposure demand a more resilient exterior envelope."
Adhering to the 2024 Building Code Compendium is essential for ensuring the durability and weather resistance of any residential exterior. At empcontracting.ca Inc. your construction contractor in London, Ontario, we specialize in implementing these technical requirements to protect your investment.
9.27.6. Lumber Siding: Dimensional and Installation Integrity
Material Quality and Thickness
Per OBC 9.27.6.1, lumber siding must be sound and free from defects like knot holes or splits that could compromise the building envelope. Standard siding types—including drop, rustic, and lapped boards—must maintain a minimum thickness of 14.3 mm and a maximum width of 286 mm. Bevel siding requires specific tapering, with a minimum 5 mm thickness at the top and up to 14.3 mm at the butt for wider boards.
Joints and Overlap Requirements
To ensure proper water shedding, siding must utilize lapped or matched joints. The OBC mandates precise overlaps: at least 25 mm for lapped bevel siding and 9.5 mm for matched siding. These standards are critical for preventing moisture ingress during the heavy rain and snow seasons common in Southwestern Ontario.
9.27.7. Wood Shingles and Shakes: Standards and Fastening
Material Grading and Width
Wood shingles and shakes must comply with CSA O118.1 or O118.2. The code requires high-grade materials, such as No. 1 or Handsplit for Western Red Cedar shakes, to ensure longevity. Shingle widths are restricted to between 65 mm and 350 mm to manage natural expansion and contraction.
Precision Fastening Techniques
Section 9.27.7.3 dictates that fasteners must be placed approximately 20 mm from each edge. For single-course applications, nails must be at least 25 mm above the exposure line. At empcontracting.ca Inc. your construction contractor in London, Ontario, we ensure these fastening patterns are strictly followed to prevent shingle uplift during high-wind events.
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.