OBC 2024 Guide: Group F Division 3 Industrial Building Requirements in Ontario
Sarah's Expert Insight
OBC Compliance Specialist
"In rapidly growing industrial hubs like London and Oakville, the distinction between 45-minute combustible and 1-hour noncombustible construction is a major budget driver. At empcontracting.ca Inc. your construction contractor in London, Ontario, we often advise clients in Muskoka and beyond that increasing street frontage is one of the most cost-effective ways to expand allowable building area without triggering the more expensive noncombustible material requirements."
Understanding the requirements for low-hazard industrial occupancies is critical for developers and builders. As empcontracting.ca Inc. your construction contractor in London, Ontario, we ensure your facility meets the strict fire safety and structural integrity standards mandated by the 2024 Ontario Building Code (OBC).
3.2.2.84. Group F, Division 3: Sprinklered Buildings Up to 6 Storeys
Buildings classified as low-hazard industrial (Group F, Division 3) that are equipped with an integrated sprinkler system are permitted to reach up to six storeys. These structures require specific safety measures to manage the large building areas associated with industrial use.
Noncombustible Construction and Fire Ratings
Under this section, buildings must be of noncombustible construction. Floor assemblies, mezzanines, and roof assemblies must maintain a fire-resistance rating of at least 1 hour. Furthermore, loadbearing walls and columns must provide a rating equivalent to the assemblies they support to prevent structural failure during a fire event.
3.2.2.85. Group F, Division 3: Standards for Up to 4 Storeys
For industrial projects that do not require six storeys or full sprinkler systems (under certain conditions), Article 3.2.2.85 provides a framework for buildings up to four storeys. This section allows for more flexibility regarding construction materials.
Combustible Construction and Area Limitations
Unlike the larger sprinklered versions, these buildings are permitted to use combustible construction. However, strict area limits apply based on the number of storeys and street access (ranging from 1,200 m² to 7,200 m²). Fire-resistance ratings for floor assemblies and mezzanines are set at a minimum of 45 minutes to ensure occupant safety.
Maximizing Site Potential via Street Access
The OBC rewards site designs that offer better fire department access. A single-storey building's allowable area can increase significantly—from 4,800 m² to 7,200 m²—simply by ensuring the building faces three streets instead of one.
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.