How to Prevent and Thaw Frozen Pipes

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How to Prevent (and Thaw) Frozen Pipes

Frozen pipes are a serious threat that can affect any Canadian home during the winter. Not only can the issue leave you without water, a frozen pipe could lead to an even bigger inconvenience – burst pipes. A burst pipe usually involves a messy clean-up, and potentially expensive property damage.

As you may remember from grade seven chemistry, while most substances contract when they freeze, water is unique because it expands. This expansion will put a great deal of pressure on whatever is holding it, including your water pipes. If this pressure lasts long enough, it can cause pipes to break – no matter how strong the pipes may be.

Pipes that freeze most frequently are those that are exposed to severe cold, including ones found in unheated areas of your home (like attics, crawl spaces and the garage), and those that run against exterior walls with little or no insulation.

Here are few tips to help protect your home from potential damage of frozen pipes.

Before a deep freeze

  • When summer garden watering is over, be sure to close inside valves supplying your outdoor hose with water, drain the line, and then disconnect the hose from the spigot.
  • Insulate all accessible pipes – especially those more susceptible to freezing. If you’re not sure how to do this or what type of insulation to use, ask at your local hardware store or call a licensed plumber.
  • Have all pipe seals checked. Be sure to repair and fill all cracks and holes you find on your home’s outside walls (note: caulk typically needs to be applied in temperatures of at least 4 degrees Celsius). Use only a sealant or caulk approved for exterior use.
  • Consider installing a water leak sensor in areas where you might expect problems. The sensor will send you an alert when water leakage is detected to allow you to act quickly on any developing problems.

When temperatures drop

  • Listen to daily weather reports, and be on alert for winter advisories and freezing temperatures. Any temperature under 0 degrees Celsius could lead to frozen pipes.
  • During severe cold, keep exterior doors to unheated spaces, like garages, closed so the cold has a harder time getting in.
  • If kitchen, bathroom, or laundry room sink pipes are located near exterior walls, leave cabinet doors open so warm air can circulate around them. Also consider using a fan to help circulate warmer air around them.
  • If you’re really concerned freezing may occur, turn taps on to a very slow drip during extreme cold snaps to help prevent water from freezing and to relieve pressure if some water does freeze. Ensure that someone is home or that a water leak sensor is installed if you choose to do this as faucets should not be left open and unattended.

Burst water pipe
How to test for frozen pipes (and how to thaw them)

  • Check your pipes by turning on the faucet (both hot and cold). If only a trickle of water comes out, or none at all, you may have a frozen pipe. The source of the freeze is most likely near an exterior wall or where the main water supply enters your home.
  • Heat up the pipe (beginning at the faucet and working toward the frozen section) using a blow dryer, or by wrapping the pipe with towels soaked in hot water. Never use an open flame torch to heat a pipe up.
  • Keep the faucet open as you treat the pipe. Water will begin to flow more steadily as ice melts. The running water will also help to speed the melting process.
  • Check all other faucets in your home. If one pipe has frozen, others may have frozen as well.

If you are unsure which pipe might be frozen, or just aren’t comfortable thawing it yourself, call a licensed plumber to come out immediately.

Going on a winter vacation?

  • If you’ll be going away for more than a couple days during colder months, consider turning off the water main and drain the water from your plumbing system (check out this video to learn how).
  • Keep your thermostat set at a temperature above 15 degrees Celsius in the home.
  • Have a responsible adult check on your home each day while you’re away to help mitigate any damage should a burst pipe occur. Be sure to check your homeowner’s policy to confirm how often your home should be checked while you are away.

Your home insurance coverage for damages due to freezing and burst pipes may be void if you are away for an extended period and did not take necessary precautions to prevent these issues, so make sure you talk to your insurance agent or broker about the best options for you and your home before you go away.