2024 Ontario Building Code: Fire-Resistance Ratings and Mass Timber Construction Standards
Sarah's Expert Insight
OBC Compliance Specialist
"The 2024 updates regarding mass timber and outlet box separation are game-changers for developers in London and the Muskoka cottage country, where timber aesthetics are highly valued. At empcontracting.ca Inc., your construction contractor in London, Ontario, we focus on the meticulous 600 mm separation and SB-2 compliance to ensure your high-end project passes fire inspections without costly retrofits."
Understanding the 2024 Ontario Building Code (OBC) is essential for any modern build. At empcontracting.ca Inc., your construction contractor in London, Ontario, we specialize in implementing these complex safety regulations to ensure your project is both compliant and durable.
Mass Timber Fire Protection and Partition Requirements
Article 3.1.6.15 outlines specific protection measures for mass timber partitions. To meet safety standards, surfaces must be protected with either 12.7 mm Type X gypsum board or 19 mm fire-retardant-treated wood. These requirements are vital for ensuring that wood-framed partitions provide the necessary fire endurance in residential and commercial applications.
Exposed Materials in Concealed Spaces
Per Article 3.1.6.16, materials within concealed spaces of floor, roof, and wall assemblies in mass timber buildings must generally be noncombustible. Exceptions exist for shallow concealed spaces (under 25 mm) when specific attachment materials are used, ensuring that fire spread risks are minimized in hidden areas of the structure.
Electrical Outlet Box Penetrations
When installing electrical components in structural mass timber, Article 3.1.6.17 dictates that outlet boxes on opposite sides of a fire-rated element must be separated by at least 600 mm. This prevents the weakening of the fire-resistance rating at penetration points, a critical detail for multi-unit builds in Ontario.
3.1.7 Fire-Resistance Ratings and Performance Testing
The determination of fire-resistance ratings is strictly governed by Article 3.1.7.1. Ratings must be established using the CAN/ULC-S101 standard, "Standard Method of Fire Endurance Tests of Building Construction and Materials," or via the MMAH Supplementary Standard SB-2.
Exposure Conditions and Exterior Wall Exceptions
Floor and roof assemblies are typically rated for fire exposure from the underside, while firewalls must be rated from both sides. For exterior walls with a limiting distance of 1.2 m or more, specific temperature rise limits may be adjusted, provided radiation calculations are performed in accordance with the OBC.
For expert guidance on these regulations, trust empcontracting.ca Inc., your construction contractor in London, Ontario, to manage your next build with precision.
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.