2024 Ontario Building Code Stucco Standards: Material, Fastener, and Lath Requirements
Sarah's Expert Insight
OBC Compliance Specialist
"At empcontracting.ca Inc., we emphasize that in regions like London and Muskoka, the freeze-thaw cycle makes the use of galvanized, corrosion-resistant fasteners and precise aggregate grading non-negotiable. Following these OBC 9.28 standards strictly prevents the 'stucco delamination' we often see in properties where substandard materials were used, ensuring your exterior remains waterproof and structurally sound for decades."
Ensuring your home's exterior meets the 2024 Building Code Compendium standards is vital for long-term durability. For those seeking professional installation, empcontracting.ca Inc. your construction contractor in London, Ontario, provides expert adherence to all OBC 9.28 regulations.
9.28.2.2. Aggregate Grading and Water Quality for Stucco
The OBC provides strict guidelines for the composition of stucco to ensure a proper bond and finish. Table 9.28.2.2 outlines the required aggregate grading, ensuring a specific distribution of particle sizes from 4 mm down to 0.125 mm. Additionally, Section 9.28.2.3 mandates that water used for mixing must be clean and free of deleterious materials that could compromise the chemical integrity of the stucco.
9.28.3. Fastener Specifications and Material Safety
Proper attachment is critical to prevent stucco failure. According to OBC 9.28.3.1, fasteners for stucco lath or reinforcing must be corrosion-resistant and specifically excluded from being made of aluminum. This prevents chemical reactions that can lead to structural weakening.
Nails and Staples Dimensions
- Nail Sizing: Nails must have a minimum diameter of 3.2 mm and a head diameter of at least 11.1 mm.
- Staple Sizing: Staples must be at least 1.98 mm in diameter or thickness.
- Embedment Depth: For vertical surfaces, fasteners must penetrate 25 mm into framing members. For horizontal surfaces, nails must be a minimum of 38 mm in length.
9.28.4. Stucco Lath Material Requirements
To resist the moisture-heavy environments of Ontario, Section 9.28.4.1 requires all lath materials to be protected against rust. Rib lath or expanded metal mesh must be galvanized or treated with rust-inhibitive paint, while all woven or welded wire mesh must be galvanized to meet compliance standards.
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.