When frigid arctic air hits, water freezes, and as it freezes, it expands, causing pipes to burst and possibly flood.
Pipes that freeze most frequently are those that are exposed to severe cold, such as outdoor hose bibs, swimming pool supply lines, water sprinkler lines and water supply pipes in unheated interior areas such as basements and crawl spaces, attics, garages or kitchen cabinets. Pipes that run against exterior walls that have little or no insulation are also subject to freezing.
Here are some tips to help prevent frozen water pipes before the temperatures drop.
Before Cold Weather
- Drain water from swimming pool and water sprinkler supply lines following manufacturer's or installer's directions. Do not put antifreeze in these lines unless directed. Antifreeze is environmentally harmful and is dangerous to humans, pets, wildlife and landscaping.
- Remove, drain and carefully store hoses used outdoors. Close inside valves supplying outdoor hose bibs. Open the outside hose taps to allow water to drain. Keep the outside valve open so that any water remaining in the pipe can expand without causing the pipe to break.
- Check around the home for other areas where water supply lines are located in unheated areas. Look in the basement, crawl space, attic, garage, and under kitchen and bathroom cabinets. Both hot and cold water pipes in these areas should be insulated. A hot water supply line can freeze just as a cold water supply line can freeze if water is not running through the pipe, and the water temperature becomes cold.
- Consider installing specific products made to insulate water pipes like a "pipe sleeve" or installing UL-listed "heat tape," "heat cable," or similar materials on exposed water pipes. Many products are available at a building supplies retailer. Pipes should be carefully wrapped, with ends butted tightly and joints wrapped with tape. Follow manufacturer's recommendations for installing and using these products. Newspaper can provide some degree of insulation and protection to exposed pipes.
- Determine where the water shut-off valve is in the house and how to use it in case pipes freeze and break.
- To find the water shut-off valve, locate the outside water line that leads to the residence. The water line usually flows directly from the water meter to a location inside the residence. Likely places for the water turn-off valve include internal pipes running against exterior walls or where water service enters a home through the foundation.
- Shut off your interior water valve before you leave for vacation to avoid flooding while you're gone.
During Cold Weather
- Keep garage doors closed if there are water supply lines in the garage.
- Open kitchen and bathroom cabinet doors to allow warmer air to circulate around the plumbing. Be sure to move any harmful cleaners and household chemicals out of the reach of children.
- When the weather is very cold outside, let the cold water drip (at a minimal amount) from the faucet served by exposed pipes. Running water through the pipe, even at a trickle, helps prevent frozen pipes.
- During extreme cold, keep the thermostat set to the same temperature both during the day and at night.
- If you will be going away during cold weather, leave the heat set to a temperature no lower than 55ºF.
Thaw Frozen Pipes
- If your house or basement is flooding, turn off the water valve and call 911.
- If there is no flooding but you turn on a faucet and only a trickle comes out, make sure your main water valve is turned on. If it is, suspect a frozen pipe. Locate the suspected frozen area of the water pipe.
- As you treat the frozen pipe and the frozen area begins to melt, water will begin to flow through the frozen area. Running water through the pipe will help melt more ice in the pipe.
- Thaw the pipe slowly, as a rapid thaw could cause the copper to split causing additional issues.
- Apply heat to the section of pipe using an electric heating pad wrapped around the pipe, electric hair dryer, a portable space heater (kept away from flammable materials), or by wrapping pipes with towels soaked in hot water. Do not use a blowtorch, kerosene or propane heater, charcoal stove or other open flame device. Make sure a heating pad, hair dryer or other electrical devices do not come into contact with water.
- Keep the faucet open. Apply heat until full water pressure is restored.
- If you are unable to locate the frozen area, if the frozen area is not accessible or if you cannot thaw the pipe, call a licensed plumber.
- Check all other faucets in your home to find out if you have additional frozen pipes. If one pipe freezes, others may also freeze.
- Ensure the water meter is not frozen. Visit bouldercolorado.gov/services/water-utility-service-disruptions for contact information.
- Consider relocating exposed pipes to provide increased protection from freezing. For example, if the home is being remodeled, a professional can relocate pipes.
- To maintain higher temperatures, add insulation to attics, basements and crawl spaces.
- For more information about frozen pipes, contact a licensed plumber or building professional.