2024 Ontario Building Code: Group B & Group C Construction Standards for Sprinklered Buildings
Sarah's Expert Insight
OBC Compliance Specialist
"Navigating the stringent fire-separation requirements for Group B and C buildings is a core competency of empcontracting.ca Inc. your construction contractor in London, Ontario. Whether we are consulting on high-density residential builds in Oakville or specialized care facilities in Muskoka, the 2-hour fire-resistance mandate in Article 3.2.2.47 remains a critical factor in project budgeting and material selection to ensure life safety and OBC compliance."
Understanding the complexities of the 2024 Building Code Compendium is essential for any major development in Ontario. At empcontracting.ca Inc. your construction contractor in London, Ontario, we specialize in interpreting these regulations to ensure your project meets all safety and structural requirements.
3.2.2.44 to 3.2.2.46: Group B, Division 3 (Care Occupancies)
Up to 3 Storeys, Sprinklered (3.2.2.44)
For buildings classified under Group B, Division 3, a height of up to three storeys is permitted if the building is sprinklered throughout. The building area is restricted based on height: 5,400 m² for one storey, 2,700 m² for two storeys, and 1,800 m² for three storeys. These structures must maintain a fire-resistance rating of at least 1 hour for floor assemblies and mezzanines.
Up to 2 Storeys and One Storey Requirements (3.2.2.45 & 3.2.2.46)
Smaller Group B developments are subject to slightly different fire-resistance mandates. For two-storey buildings up to 2,400 m², a 45-minute fire-resistance rating is required. Single-storey buildings limited to 600 m² must still be sprinklered but offer more flexibility regarding combustible construction materials.
3.2.2.47: Group C (Residential Occupancies)
Any Height, Any Area, Sprinklered
Article 3.2.2.47 governs major residential buildings (excluding retirement homes which have specific exceptions). These buildings must be of noncombustible construction and sprinklered throughout. Key requirements include:
- Floor assemblies must act as fire separations with a fire-resistance rating of at least 2 hours.
- Mezzanines must have a fire-resistance rating of at least 1 hour.
- All loadbearing walls, columns, and arches must match the fire-resistance rating of the assembly they support.
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.