Backwater valves · Toronto & GTA
Backwater valve installation in Toronto — permit, install and subsidy paperwork done for you
Stop sewage from coming up through your floor drain during a storm. We pull the permit, install the valve, book the inspection and give you everything the City needs for the flood subsidy.
Is it for you
Who needs a backwater valve?
If any of these describe your home, a backwater valve is the single best flood protection you can buy.
You have flooded before
Once a sewer has backed up into your basement it will do it again in the next big storm.
Finished basement
Drywall, flooring and furniture turn a sewer backup into a five-figure insurance claim.
Older street
Pre-1980 neighbourhoods with combined sewers overload first in heavy rain.
Insurer asked for one
Many Ontario insurers now ask for a backwater valve before renewing sewer-backup coverage.
Floor drain gurgles in storms
That sound is the sewer pushing back. The valve closes before water gets in.
Buying an older home
Adding a valve during a reno is cheaper than after the basement is finished.
How we do it
How is a backwater valve installed?
One day, one crew, done to code and inspected.
- Camera inspection of the main line first, so we know the pipe is sound before cutting the floor.
- Permit pulled with the City before work starts.
- Normally-open valve installed on the main line with a removable access cover.
- City inspection booked and attended by us.
- Subsidy package: invoice, permit and photos, ready for your online application.
Pair it with a sump pump
If your weeping tile drains into the sewer, a backwater valve alone can trap water outside. A sump pump solves that, and both are subsidy-eligible.
Pricing
How much does a backwater valve cost in Toronto?
Installed price including permit, inspection and concrete patch.
| Job | Typical range |
|---|---|
| Mainline backwater valve | $2,500 – $4,500 |
| Sewer camera inspection (before install) | $280 – $450 |
| Valve check and cleaning | $150 – $250 |
The City of Toronto subsidy can cover part of this cost. See the subsidy guide.
FAQ
Common questions
What is a backwater valve?
A backwater valve is a one-way flap installed in your main sewer line. Wastewater leaves the house normally, but when the municipal sewer backs up during a storm, the flap closes and stops sewage from coming up through your basement floor drain.
How much does a backwater valve cost in Toronto?
A mainline backwater valve typically costs $2,500 to $4,500 installed, depending on how deep the line is and what the floor is made of. Part of that can be recovered through the City of Toronto Basement Flooding Protection Subsidy.
Do I need a permit for a backwater valve?
Yes. In Toronto a backwater valve installation needs a plumbing permit and an inspection. We pull the permit and book the inspection as part of the job.
How long does installation take?
Usually one day. We break the floor near the main stack, install the valve with an access cover, backfill and patch the concrete the same day.
Does a backwater valve need maintenance?
Yes, a quick check once or twice a year: open the access cover, make sure the flap moves freely and nothing is caught in it. We show you how on the day of the install.
Get flood-ready before the next storm
Book a free assessment. We tell you what your home needs and what the City will pay back.