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Home » Know Your Main Water Shut Off Valve? The Complete Guide for Homeowners
The main water shut off valve is the master switch for your home’s entire plumbing system, and it is installed in every home. They can be of different sizes and types depending upon the location and city upgrades, but every home must have one. No bypass is allowed; it’s a law. This water shut off valve to the house helps to control municipal water into your home. The main water shut off valve has different names as well, such as a water meter valve, water main valve, or simply a water main shut off.
Locating the main water shut off valve is not as hard as you think. This is usually installed near the wall, or sometimes even inside, where the city pipe enters your home next to the water meter. But remember, the water main shut off valve is never installed outside your exterior wall. In Canada, this valve is almost always located indoors to prevent the line from freezing, as we have harsh winters.
The main water shut off valve is usually located inside the house near the front wall beside the meter. Most people have this installed in the mechanical room as well. Some people hide this valve behind the drywall, and some valves could even be buried under concrete or rarely seen hiding halfway in the concrete floor; this happens when a homeowner or contractor does not think about its importance.
If you are having a hard time spotting the valve, do this: follow the pipe. Look for the pipe entering the home (it can be PEX or copper) through the foundation wall. If you follow it to the point where it reaches the hot water tank or the nearest fixture, it means the valve is inside the wall where the pipe first enters your home.
Common spots: Check near the water heater, under the front stairs, or nearby the cold room in the basement—or in the crawl space if you have one.
The shape, type, and size of every main water shut off valve could be different. This is due to the city water line size coming to the house and the choice of valve by the owner or contractor. Usually, most neighbors in Toronto have a 1/2” size shut off valve, whereas the majority of neighbors’ Toronto water lines are being updated to sizes ranging from 3/4” to 1”.
The valves that are commonly used for a main water shut off valve are ball valves or gate valves. These are the two types of valves found in Ontario homes:
Awarded in 2021 for an Outstanding Toronto Plumber by Homestars
Being a Toronto plumber, we have seen that most homeowners never see their main water shut off. We usually ask our clients about it while replacing their fixtures, and most times they get confused.
The main water shut off valve has significant importance, as it’s the master switch that you can touch to control the water flow in the house. In an emergency situation—like a water pipe burst, a pipe leaking, or any fixture malfunction—your first line of defense for any unknown leak found in the home is your water main shut off. As soon as you turn it off, water will completely stop flowing inside. In any plumbing emergency situation, turning off the water main shut off valve can help you protect your home from costly repairs and damage.
It is also important to check and test your water shut off valve to house time and again so you are prepared for an immediate response in an emergency situation. We have seen a number of clients in Toronto residences who are unable to turn off their shut-off valve because it has never been used; due to aging, it gets jammed, which makes it hard to turn on and off.
In an emergency—like a water pipe burst—turning off the valve is critical. If the damage has already started, we offer expert water pipe burst and frozen pipe repair in Toronto to get your home back to normal.
As the main water shut off valve is the only valve that a homeowner or contractor has the right to turn on and off in any situation, things change if it starts leaking. In this case, you must call the city to turn off the water from the city side at the curb.
The city has its own city water shut off valve for each home; it is called a curbside valve. You may have seen or noticed this in your front yard, on the sidewalk, or near the property line in front.
You must call the city at 311 and ask for an emergency response to turn on or off the water from the outside. Explain what is happening and what damage it is causing, and the city will turn it off within a couple of hours of your call. Once you call the city, you should contact a licensed and authorized plumber, like Everest Plumbing, to replace the main water shut off valve inside your home. We are fully equipped and licensed to help you with a water main valve replacement for any size or type the same day you call—that is the Everest guarantee.
The city water shut off valve, also known as the curbside valve, is the valve controlled by the city to supply water to your house. This is usually located outside your home in the front yard or on the sidewalk, before your main water shut off valve. Curbside valves are usually located below the frost level at 4 feet deep, but the city has special long extension keys to turn them off from the ground surface. Only the municipality or city has the authority to turn these valves on or off. Anything involving tampering with the city water shut off valve can have serious legal consequences.
Besides the main water shut off valve, there are a number of other shut-off valves you can find in your home. These are usually found near your fixtures and appliances. These valves are usually 1/2” or the size of the fixture inlet pipe. These valves are specifically installed to control water flow to each individual fixture.
You must consider installing a shut-off valve for every fixture; in this way, you have control over the water to that fixture in any emergency situation where it malfunctions. You can turn off the water for that fixture only—no need to turn the main water shut off for the entire home. This allows you to continue using water in the rest of the house by turning off only the water for the malfunctioning fixture or appliance.
Branch lines to the outdoor garden, another floor, or a garden suite also must have separate shut-off valves to control water flow. This also helps to winterize your system by turning it off during the winter, preventing pipes from bursting in the harsh winter.
The average cost to replace a main water shut off valve in Toronto is between $180.00 and $480.00, depending on the type and location of the valve.
Usually, shut-off valves for fixtures, which are typically 1/2” to 3/4” in size, will cost you around $180.00 to $380.00. In contrast, the main water shut off valve replacement cost for sizes up to 1” is approximately $380.00 to $480.00, depending on how accessible the valve is. Please note that there is a variety of valve brands on the market; prices may vary depending on the quality.
If you’re wondering who is responsible for replacing the main water shut off valve, the homeowner is responsible for the valve and piping inside the property line, while the city manages the city water shut off valve at the curb. Check the official guidelines on pipe leak or burst responsibilities to see where the city’s job ends and yours begins.
Need exact pricing for your water main valve replacement? Call us now or simply send us an image of your valve. We will provide an exact price before a technician is dispatched anywhere in the Greater Toronto Area.
In Toronto and across Ontario, the homeowner is responsible for the main water shut off valve located inside the house, as well as all plumbing from the property line inward. The City is responsible for the city water shut off valve (curbside valve) located at the property line or sidewalk.
As of 2026, the City of Toronto charges a Water Turn-off/Turn-on Fee of $110.13. This fee is typically added to your utility bill. However, the fee may be waived if the water is being turned off to repair a leak found on the City’s side of the property
Because this valve controls the entire water supply and requires a city water shut-off at the curb to be replaced safely, it is highly recommended to hire a licensed plumber. In Ontario, plumbing work must comply with the Ontario Building Code, and a faulty installation could lead to major flooding that insurance may not cover if performed by an unlicensed individual.
Older gate valves (with the round wheel handle) are notorious for seizing or “bottoming out” due to mineral buildup and age. If your valve is stuck, do not force it, as the internal stem can snap, leaving your water stuck in the “on” or “off” position. This is a clear sign you need a water main valve replacement.
You should “exercise” your valve at least twice a year. Gently turn it off and back on to ensure the internal parts aren’t seizing. This simple habit ensures that you are prepared for a real plumbing emergency.
Yes. Modern plumbing standards in Ontario favor ball valves. They are more reliable, last longer, and allow you to see at a glance if the water is on or off. If you still have an old-style gate valve, you should consider a main water shut off valve replacement to a ball valve for better home safety.
If you cannot find your city water shut off valve or it has been paved over, call 311 to notify the City of Toronto. It is the homeowner’s responsibility to ensure the City has access to this valve. If they have to dig to find it during an emergency, it could result in extra costs to repair your driveway or landscaping.
