With heavier rains, when are full‑port backwater valves required by OBC/municipal bylaws; and should you choose normally open vs branch valves?
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Okay, here’s a simpler version of that text:
When do you need backwater valves?
In Ontario and a lot of cities, you usually need full-port backwater valves if your basement plumbing could get hit by sewage backup. This is super important if you’re in an area that gets a lot of rain or has combined sewer issues.
Usually, local rules say you need them for new buildings, big renovations, or if you’re changing storm or waste connections, mostly if your basement stuff is lower than the street sewer.
Normally open vs. branch valves:
Normally open valves on the main drain let water flow as usual but close automatically if sewage backs up. They’re your main defense.
Branch valves look after single lines, like a floor drain or laundry. Use them if a main valve can’t protect everything or if you need to protect just one area.
Basically, protect the main line with a full-port, normally open valve. If some fixtures are still at risk, add branch valves for those.
Full-port backwater valves are required by municipal bylaws in specific situations, particularly when:
-Flooding Risk is High: Areas prone to basement flooding or with combined sewer systems may mandate the installation of backwater valves to prevent sewage backup.
-Low Elevation: Properties with plumbing fixtures below the elevation of the manhole cover of the next upstream manhole in the public sewer may require backwater valves.
OBC/municipal rules require full-port backwater valves when basements are below sewer level or at risk of surcharge. Normally closed, full-port valves are preferred for flow and code compliance, with easy maintenance access.
When required: Full-port backwater valves are needed for basement drains below surcharge level in areas prone to heavy-rain sewer backup.
Type: Use normally open on the main line for full protection; branch valves only protect specific fixtures.
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OBC/most bylaws require full-port backwater valves on sanitary lines where flood risk exists; choose normally open for whole house, branch valves for isolated fixtures.
In areas with heavier rains, full-port backwater valves are often required by the OBC and municipal bylaws to prevent sewage backup into homes. Generally, normally open backwater valves (those that are open by default and close when backflow occurs) are preferred, though specific requirements can vary by municipality. It’s crucial to consult local bylaws and potentially seek professional advice to ensure compliance and proper installation, as improper installation can lead to bypass or even basement flooding