Why this matters
The valve’s flap or gate must move freely and seal fully. Debris such as grease, wipes or sediment can hold it open, and a valve that cannot close will not stop a sewer backup. Many valves installed in Markham basements under subsidy programs are now several years old and have never been opened.
Know your valve
| Feature | What it does |
|---|---|
| Access cover | Lets you see and reach the valve |
| Flap or gate | Closes when sewage flows backward |
| Floats | Lift the flap as water rises |
| Clear lid | Lets you view the flap on some models |
Red flags around the house
- Pump short-cycling every few seconds.
- A humming motor with no water moving.
- Damp walls or efflorescence near the pit.
- Water returning up the floor drain in a storm.
Step by step
- Avoid using water in the house during the check.
- Remove the floor access cover and the valve’s lid as the maker describes.
- Wear gloves and eye protection; the inside is part of your sewer.
- Check the flap moves up and down freely and seats properly.
- Remove any debris and rinse the flap gently with a hose or bucket.
- Check the lid’s gasket, refit it securely and replace the cover.
Handing it over to us
Call if the flap is cracked, the lid will not seal, sewage is visible above the valve, or you cannot find an access cover. See backwater valve installation and early signs of a sewer backup.
Markham note: village-core houses tend to hide cast iron and galvanized behind plaster, while Cornell and Box Grove builds run PEX to a manifold. We ask the year your house was built so the right fittings ride along on the truck.
Straight from the phone log
Is twice a year really enough for the valve?
At least twice a year, and before a forecast of heavy rain.
Why does my valve smell?
A poorly seated lid or gasket can let odours out. Replacing the gasket often fixes it.
Ready to get it fixed?
One call, a clear explanation, and work finished tidily before we leave.