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Frozen Water Pipes

Water service connections in Montréal are located underground, at a depth of between 1.6 and 2.0 metres. During the winter, frost can penetrate into the ground up to 1.63 metres in depth. Water service connections located more toward the surface may therefore be subject to frost.

What is a water service connection? A residential water service connection is a pipe—50 mm in diameter or less—that connects a building to the public water service line, which is usually located under the street. The residential water service connection supplies all the apartments of a building with drinking water.


Six actions to take to prevent your water service connection from freezing (before the very cold weather sets in)

1. Locate the main water valve inside your home and allow clear access.

2. Make sure that the ambient temperature near the valve is at least 10 degrees Celsius.

3. Insulate the pipes that are most susceptible to freezing, especially those that are near exterior walls and in the crawlspace, attic or garage. You may use foam insulating pipe covers, available at home renovation or hardware stores.

4. Seal air leaks around your house and garage to prevent cold drafts.

5. Check for air leaks near windows, doors, electrical wiring and dryer exhaust.

6. Remove garden hoses, cut off the water supply and drain the pipes before the first frost.

Three recommendations in very cold weather

1. Keep the kitchen cupboard and bathroom doors open to allow warm air to circulate around pipes.

2. Have someone you trust check on your home regularly.

3. Let the water trickle* from your taps continuously, to keep the water flowing in the pipes and avoid freezing.

*Prevent flooding by ensuring that your drains are not blocked.

If you turn on the tap and no water or almost no water comes out, your pipes are probably frozen. You must act quickly to prevent your pipes from bursting.


Four steps for unfreezing your pipes

1. Turn on the taps.

2. Find the frosted or frozen section of the pipe that is connected to the faucet. The pipe may be slightly curved or cracked.

3. Use a hair dryer or backup heating system to heat the frozen section of the pipe. You may also use electric heating tape.

4. If these techniques do not work, call your borough at 311, or contact a plumber (calling a plumber involves costs).