Every Homeowner Should Know Where Their Water Shutoff Is

When a supply line bursts under a sink or a toilet inlet valve fails, the first thing a plumber will ask is: "Have you shut off the water?" If you don't know the answer, damage accumulates while you figure it out. Every homeowner should take five minutes to locate and test their water shutoffs before an emergency requires it.

The main shutoff controls water to the entire property. In most Lower Mainland homes, it's located where the service line enters the building — typically in a utility room, crawl space, or near the water meter. In some older or strata properties, it may be at an exterior meter pit. The main shutoff is usually a gate valve (round wheel handle) or ball valve (lever handle). Ball valves are more reliable — a quarter turn closes them completely. Gate valves can seize if not operated regularly.

Most homes also have zone shutoffs at each fixture or appliance — under sinks, at toilets, behind washing machines, and at the water heater. These allow you to isolate a single fixture without shutting off the whole house. Check that each one turns freely: stuck shutoff valves are extremely common in homes that haven't had plumbing work in years. A valve that won't close during an emergency is useless.

• Operate every shutoff valve once a year — just a full open-to-close-and-back cycle is enough to prevent seizing.
• If a valve is stiff, leaking at the packing nut, or won't close fully, have it replaced before you need it.
• Label any unlabelled shutoffs with a marker or tag so any household member can find and use them quickly.
• Know the location of the municipal curb stop (the shutoff at the property line) in case the main shutoff inside the home fails. The city controls this valve, but knowing where it is helps in an emergency.

Once you've shut the water off, call a licensed plumber. Before reopening the supply, check the affected area thoroughly for standing water — moisture behind walls or under flooring that isn't dried quickly leads to mould. Don't restore water pressure to a burst or failed line without the repair confirmed complete.