Ontario Building Code HVAC Standards: 2024 Ductwork and Insulation Requirements
Sarah's Expert Insight
OBC Compliance Specialist
"In regions like London and Muskoka, the interaction between high humidity and HVAC insulation is a frequent point of failure in older builds. By strictly adhering to the 2024 OBC's foamed plastic restrictions and flame-resistance standards, empcontracting.ca Inc. your construction contractor in London, Ontario, ensures your project remains both code-compliant and fire-safe for the long term."
Navigating the 2024 Building Code Compendium is essential for ensuring the safety and efficiency of residential and commercial HVAC systems. As part of our commitment at empcontracting.ca Inc. your construction contractor in London, Ontario, we ensure every installation meets the rigorous standards set out in Section 9.33.6.
Duct Material Durability and Corrosion Resistance
According to OBC 9.33.6.2, all duct materials and fittings must be selected based on their ability to withstand the specific temperature and humidity levels of the air they convey. In regions with varying seasonal climates, resistance to corrosion from airborne contaminants is a critical safety requirement.
Moisture Exposure Standards
For ducts installed in environments prone to moisture, materials must retain their structural strength when wet and remain corrosion-resistant to prevent degradation over time, protecting the overall air quality of the structure.
Flame-Resistant Sealing and Tape Standards
OBC 9.33.6.3 mandates that any tape used for sealing joints in air ducts, plenums, or other system parts must meet the flame-resistance standards of CAN/ULC-S109. This ensures that the ductwork system does not facilitate the spread of fire within the building envelope.
Foamed Plastic Insulation Requirements
Section 9.33.6.4 places strict limitations on the use of foamed plastic insulation. Generally, foamed plastic is prohibited unless specific safety criteria are met, particularly regarding proximity to heat sources:
- Insulation must be at least 3 meters from the furnace bonnet.
- Internal duct temperatures must not exceed 50°C.
- Joints must be sealed with approved flame-resistant tape per Sentence 9.33.6.3.(1).
- Protection must be provided in accordance with fire safety article 9.10.17.10.
Specifications for Metal Supply Ducts
Standard galvanized steel or aluminum supply ducts must conform to Table 9.33.6.5 and ANSI/SMACNA 006 standards. These regulations dictate the metal thickness and fitting design necessary to maintain system pressure and structural integrity throughout the life of the building.
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.