Homeowner notes
How to Find and Test Your Main Water Shut-Off
Everyone old enough to be home alone ought to be able to close the main water valve. Track it down today, on a dry afternoon.
- Plain steps a homeowner can follow
- Where the DIY part ends and a plumber takes over
- Ontario and GTA details where they matter
- Plumbing facts, no sales pitch
Diagnosis first, tested after
- Licensed & insured: ask us
- Camera before cutting
- Water-tested repairs
- Booked by phone
Where to look
The main valve is almost always where the water service enters the house. In most GTA homes with basements, that is the front foundation wall, facing the street, often near the water meter. Look behind furnace rooms, under basement stairs, inside a closet built around the meter, or behind a removable panel in a finished wall. Slab-on-grade houses and some townhomes hide it in a mechanical closet, frequently beside the water heater.
- Front basement wall
- Next to the water meter
- Under stairs or behind panels
- Mechanical room in newer homes
Types of valve
| Valve | How to close | Notes |
|---|---|---|
| Gate valve (round wheel) | Clockwise until it stops | Older; prone to seizing and incomplete shutoff |
| Ball valve (lever) | Quarter turn, lever across pipe | Reliable; common replacement |
| Curb stop (outside) | Special key; city-owned | For the municipality or a plumber |
Test it
Shut it, then try an upstairs tap. After a sputter the flow ought to die away inside a minute; a steady stream means the gate inside is no longer seating. Reopen slowly. Old gate valves sometimes leak at the stem after being turned; a small drip can often be stopped by gently snugging the packing nut. A seized valve, or one that lets water past, is due for replacement, which we do routinely.
A valve you have never closed is a valve you cannot count on.
Label and share
Hang a tag on the valve. Show everyone in the house, including teenagers and tenants. Keep the area clear of storage. If you rent out a unit, tell the tenant where it is. If yours is buried behind finished drywall, add an access panel.
When to call
If you cannot find the valve, or it does not work, call (365) 387-8531 and we will locate or replace it.
Stop and call a plumber if
- Green crust on copper joints or rust weeping from galvanized fittings
- Water bill climbs with no change in use
- Meter dial creeps with every tap closed
Common questions
Can I use the curb stop myself?
The curb stop is usually municipal property. Contact your municipality or a plumber to operate it.