2024 Ontario Building Code Guide: Plumbing Traps and Drainage Standards for London Construction
Sarah's Expert Insight
OBC Compliance Specialist
"In the London and Oakville markets, we often see issues with trap seals drying out in basement mechanical rooms, leading to unwanted odors. At empcontracting.ca Inc., we prioritize the installation of high-quality trap seal primers as per OBC 7.4.5.5 to ensure that even during dry seasons or in seasonal Muskoka properties, the plumbing system remains safe and odor-free."
Mastering OBC Plumbing Standards with empcontracting.ca Inc.
Navigating the 2024 Building Code Compendium is a critical step for any successful build. At empcontracting.ca Inc. your construction contractor in London, Ontario, we ensure every project adheres to the rigorous drainage and trap requirements specified in Division B – Part 7.
7.4.5.1 & 7.4.5.5. Dishwasher Connections and Trap Seals
For domestic dishwashing machines, the code requires the drainage pump discharge line to rise as high as possible under the counter. This prevents backflow and ensures a direct, safe connection to either a Y-fitting on the sink trap inlet or the disposal unit. Furthermore, trap seals for floor or hub drains must be maintained via trap seal primers or indirect drinking fountain connections to prevent sewer gas entry.
7.4.5.2. Storm Drainage System Requirements
When storm drainage systems connect to combined sewers, specific trap installations are mandatory. However, exceptions exist for roof leaders that terminate at weather-protected roofs, provided they maintain a distance of 1 m from air inlets and 1.8 m from property lines. Floor drains entering storm systems must be protected by a trap, though these typically do not require a vent pipe.
7.4.5.3. Subsoil Drainage and Sanitary Connections
The OBC is strict regarding foundation and subsoil drainage. Generally, these should not connect to sanitary systems. However, in specific cases where soil conditions prevent drainage to a culvert or dry well, a connection may be permitted on the upstream side of a trap with a cleanout or a trapped sump.
7.4.5.4. Building Traps and Cleanout Locations
When a building trap is required, it must be installed with a cleanout fitting directly over the trap on the upstream side. For maximum accessibility and code compliance, these must be located inside the building as close as possible to the exit point of the building drain or housed in an external manhole.
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.