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Ontario Building Code Section 7.7: Non-Potable Water System Regulations for London Contractors

Ontario Building Code Section 7.7: Non-Potable Water System Regulations for London Contractors
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Sarah's Expert Insight

OBC Compliance Specialist

"Strict compliance with Section 7.7 is crucial for London and Oakville developers looking to implement greywater recycling or sustainable irrigation. At empcontracting.ca Inc. your construction contractor in London, Ontario, we emphasize the importance of distinct marking and backflow isolation to ensure these eco-friendly systems never compromise a building's potable water integrity."

OBC Section 7.7.1: General Requirements for Non-Potable Systems

According to the Ontario Building Code (OBC), non-potable water systems must be designed, fabricated, and installed following good engineering practices. At empcontracting.ca Inc. your construction contractor in London, Ontario, we ensure that these systems are strictly limited to approved applications such as water closets, urinals, trap seal primers, and underground irrigation systems that dispense water below the surface.

Pressure and Safety Limits

To ensure system longevity and safety, the OBC mandates a pressure-reducing valve if static pressure exceeds 550 kPa. Furthermore, healthcare facilities are strictly prohibited from using non-potable water systems for any fixtures. When rainwater systems are used for clothes washers, specific dual check valve backflow preventers (CSA B64.6) are required for both area and premise isolation.

Identification, Marking, and Signage

Proper identification is a critical safety component of the OBC. Non-potable water piping must be identified by permanent, distinct markings in accordance with CAN/CSA-B128.1. A mandatory warning sign must be posted above every fixture receiving non-potable water, stating: NON-POTABLE WATER, DO NOT DRINK. These letters must be at least 25 mm high with a 5 mm stroke for maximum visibility.

Location and Discharge Prohibitions

To prevent cross-contamination, the Ontario Building Code dictates strict location requirements:

  • Piping: Must not be located above food/drink preparation areas, potable water tanks, or food-handling equipment.
  • Outlets: Must not be located where they can discharge into a sink, lavatory, or any fixture connected to a potable water system.

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.

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