OBC 2024 Guide to Non-Potable Rainwater Harvesting | empcontracting.ca Inc.
Sarah's Expert Insight
OBC Compliance Specialist
"In high-growth areas like London and Oakville, rainwater harvesting is becoming a standard for sustainable residential and commercial builds. As a senior consultant at empcontracting.ca Inc. your construction contractor in London, Ontario, I emphasize that the 2024 updates require rigorous engineering to ensure harvested water is treated properly and never cross-contaminates potable lines, which is vital for long-term property safety and code compliance."
Understanding the 2024 Ontario Building Code (OBC) requirements for rainwater harvesting is essential for modern sustainable development. Subsection 7.7.2 provides strict guidelines for the design and installation of systems meant to repurpose storm water from roof surfaces for non-potable use.
Defining Non-Potable Rainwater Harvesting (OBC 7.7.2.1)
Under the code, rainwater is specifically defined as storm water discharged from above-ground roof surfaces. A compliant harvesting system includes storage tanks, pumps, and plumbing appurtenances. When planning these systems, consulting with empcontracting.ca Inc. your construction contractor in London, Ontario ensures your project remains compliant with Part 7 plumbing standards.
Permitted Applications for Harvested Water
Harvested rainwater cannot be used for human consumption. According to OBC 7.7.2.2, it is strictly permitted for:
- Water closets and urinals
- Clothes washers and laundry trays
- Floor-mounted service sinks
- Irrigation and hydronic systems
- Trap primers and make-up water for heat rejection
Roof Design and Material Safety (OBC 7.7.2.3)
The code mandates that roof surfaces used for collection must be inaccessible to vehicular or pedestrian traffic to prevent contamination. Furthermore, all roofing components must be made of materials that do not introduce harmful substances into the water supply, preserving its quality for the intended end use.
System Engineering and Treatment (OBC 7.7.2.4)
Every system must be designed and installed according to good engineering practice. A critical requirement is the inclusion of treatment systems to ensure the water quality meets provincial standards. For professional implementation, empcontracting.ca Inc. your construction contractor in London, Ontario provides the expertise needed to navigate these complex technical requirements.
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.