OBC 2024 Standards: Water Efficiency and Relief Valve Requirements for Ontario Construction
Sarah's Expert Insight
OBC Compliance Specialist
"Adhering to the 4.8 LPF standard for Group C occupancies is critical for sustainable urban development in London and Oakville. As empcontracting.ca Inc. your construction contractor in London, Ontario, we prioritize these safety and efficiency codes to ensure every plumbing installation—from high-pressure relief valves to drainage air breaks—meets the highest provincial standards for long-term reliability in city homes and Muskoka cottages alike."
Understanding the 2024 Ontario Building Code (OBC) is essential for any renovation or new build. At empcontracting.ca Inc. your construction contractor in London, Ontario, we ensure every project meets these stringent water conservation and safety regulations.
Section 7.6.1.6: Maximum Water Usage per Flush Cycle
The OBC sets strict limits on the Litres Per Flush (LPF) for sanitary fixtures to promote water conservation across the province.
Standard Occupancy Water Usage (Table 7.6.1.6.-A)
- Water Closets (Tank Type and Direct Flush): Maximum 6.0 LPF
- Urinals (Tank Type and Direct Flush): Maximum 1.9 LPF
Residential (Group C) Occupancy Requirements (Table 7.6.1.6.-B)
Residential requirements are even more rigorous to ensure sustainability in housing developments:
- Water Closets: Maximum 4.8 LPF (Note: Dual flush models offering 4.1 LPF or less and 6.0 LPF are also compliant).
- Urinals: Maximum 1.9 LPF
Section 7.6.1.7: Relief Valve Safety Standards
Proper installation of relief valves is a critical safety measure to prevent pressure-related failures in plumbing systems.
Pressure and Temperature Relief Requirements
- Pressure-Relief Valves: Must be installed on every pressure vessel to ensure pressure does not exceed 1100 kPa or 50% of the maximum test pressure.
- Temperature-Relief Valves: Storage-type service water heaters must have a sensor located within the top 150 mm of the tank, designed to discharge if temperatures exceed 99°C.
Installation and Drainage Specifications
Pipes conveying discharge from these valves must meet specific criteria to ensure safety:
- Must be rigid and at least the same nominal size as the valve outlet.
- Must slope downward and terminate with an indirect connection above a floor drain or sump.
- Must maintain an air break of no more than 300 mm.
- Must be rated for temperatures of at least 99°C.
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.