OBC Group A, Division 1 Fire Safety Guide | empcontracting.ca Inc. your construction contractor in London, Ontario
Sarah's Expert Insight
OBC Compliance Specialist
"When designing assembly spaces in London or Muskoka, the choice between noncombustible and heavy timber construction is a critical financial and architectural lever. At empcontracting.ca Inc., we see many developers overlook the 300-occupant threshold in Article 3.2.2.22, which allows for more cost-effective combustible construction if grade-level restrictions are met, significantly impacting the viability of smaller performing arts projects."
Understanding OBC Section 3.2.2.20 to 3.2.2.22 for Assembly Occupancies
Navigating the 2024 Building Code Compendium for Group A, Division 1 buildings requires a deep understanding of fire-resistance ratings and construction types. Whether you are developing a theater, cinema, or a major performing arts center, empcontracting.ca Inc. your construction contractor in London, Ontario is here to ensure your project remains compliant and safe.
3.2.2.20. Large Scale Assembly: Any Height and Area
For high-capacity assembly buildings, the Ontario Building Code (OBC) mandates noncombustible construction. Key safety requirements include:
- Automatic sprinkler systems throughout the entire building.
- Floor assemblies acting as fire separations with a minimum 2-hour fire-resistance rating.
- Mezzanines must maintain a 1-hour fire-resistance rating.
- Loadbearing walls and columns must match the rating of the assembly they support.
3.2.2.21. One-Storey Buildings with Limited Area
Small-to-mid-sized projects may qualify for less restrictive construction types. If the building area is under 600 m² and the occupant load is 600 or fewer, the code permits heavy timber construction. This is a popular choice for boutique venues in the London and Oakville areas that want a specific aesthetic while maintaining a 45-minute fire-resistance rating on floor assemblies.
3.2.2.22. Small One-Storey Assemblies and Combustible Construction
For intimate venues where the occupant load is 300 or less, the OBC permits combustible construction. This classification requires that no part of the auditorium floor be more than 5 meters above or below grade. Loadbearing elements in these structures must typically provide a 45-minute fire-resistance rating to ensure safe egress for occupants during an emergency.
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.