What to Know About Frozen Pipes
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Don't let frozen water pipes cause a flood. Here's what to know about frozen pipes, including how to prevent them and minimize damage.
For people in the U.S. southern plains states, Valentine’s Day weekend of 2021 proved memorable in an unexpected way, as a ferocious snow and ice storm coupled with sustained freezing temperatures left millions without power. Apart from rolling blackouts, the other big problem for this storm-battered region was frozen and burst water pipes. That added to the billions of dollars of damage the storm caused.
Why Do Pipes Freeze?
Water pipes can freeze when exterior temperatures drop below freezing. Pipes that are uninsulated or run through unheated areas of a home, such as an attic, garage or basement — especially if you have a sump pump — are more susceptible to freezing. So are pipes in exterior walls.
As we saw in Texas this year, power outages, coupled with extreme cold, reduced indoor temperatures to the point that interior pipes froze and burst as well.
“When pipes freeze and burst, it’s usually due to the immense pressure between the ice blockage and the closed faucet,” says bluefrog Plumbing + Drain president Mike Mushinski. “A blockage forms when motionless water settles and succumbs to the temperatures.”
Pipes often burst as temperatures start to warm up and sections of frozen pipe begin to melt, creating those pressure points strong enough to cause ruptures.
How Do I Know If I Have Frozen Pipes?
If exterior temperatures are below freezing or starting to warm back up, look for these telltale signs of frozen pipes:
- Little or no water. If it’s below freezing outside and you open the faucet and nothing comes out, or water just trickles, something’s amiss.
- Bulging pipes. As we all learned in grade school, ice takes up more space than water. Frozen pipes may noticeably bulge, even if they haven’t burst.
- Banging and gurgling sounds. If the pipes make a lot of noise when you open a faucet or flush the toilet, this can be a sign you’ve got ice traveling through your pipes.
- Condensation and cracks. If you spot a pipe that’s covered with frost or condensation, or has small surface cracks, it’s likely frozen inside.
- Smelly drains. This is a nasty one. A funky smell coming out of faucets and drains can signal a frozen exterior sewer line.
How to Keep Pipes from Freezing
As temperatures start to drop, take some preventative steps to keep your pipes from freezing and bursting.
- Keep the garage door closed. “One of the easiest ways to freeze your pipes is to allow them to be continuously exposed to the elements,” says Mushinski. “By leaving your garage door open to the brisk air, you’re doing just that.”
- Wrap exposed water pipes with pipe insulation. If the situation is urgent and you can’t get to the home center for pipe insulation, use old rags, towels and blankets.
- Let the water drip. If you’re going to be away from home, or you’re at home in the middle of an extreme winter storm, open faucets so that a slow drip of water comes out. Water that’s moving won’t freeze as readily as motionless water.
- Open the cabinets. “Pipes underneath your sinks are some of the most likely to freeze,” says Mushinski. “Wherever you have plumbing underneath your sinks or inside a cabinet, open the doors and allow the warm air to circulate, especially on cold days and nights.”
- Keep the indoors warm. Assuming there’s no massive power outage, keep the thermostat in your home at a steady temperature. If you’re going out of town or closing up a cabin or vacation home, set the heat no lower than 55 degrees F.
How to Unfreeze Frozen Pipes
If you’ve confirmed you have frozen pipes, you need to do some quick intervention to safely thaw them before they burst.
Once you’ve found the trouble spot(s), Mushinski recommends opening the hot and cold water faucets, then warming up the house or room by turning up the thermostat or bringing in a portable heater. Then, get busy thawing those pipes with one of the following tools:
Mushinski says hot towels will also work in a pinch. He suggests starting the thawing process on the end of the pipe closest to the faucet, then working toward the blockage. “This will ensure that the melting ice is able to escape through the open faucet,” he says.
Here’s another trick: Put a cookie sheet, aluminum foil or another type of metal sheet between the pipe and the wall. That keeps the heat contained in the frozen area.
What to Do If Pipes Burst
If the worst happens and one or more pipes burst, take immediate action to reduce costly damage.
- Shut off the power. Turn off power at the main switch to avoid wire damage and electrocution.
- Turn off the water. Shut off water to the affected area or to the whole house, as needed.
- Minimize damage. Get your belongings up and out of the way, Mushinski says, especially items that absorb water and may get more soaked as time passes.
- Mop up. Pump out water if needed, or mop it up and dry with fans. Once you’ve done the initial triage, Mushinski says keep the air moving with fans or a dehumidifier.
- Call the insurance company. If you’ve called an emergency plumber, Mushinski suggests you call your homeowners insurance company while the plumber is there and let them describe the extent of the damage. “It’s important to get your claim in motion as soon as possible, to help you organize remediation, clean-up and sanitizing, all of which can be more extensive than you expect,” says Mushinski.
- Document everything. Take photos, video and detailed notes of all the water damage to your home and personal items. “Include walls, floors, furniture, electrical outlets, clothes and anything the water affected,” Mushinski says.
Once things start to warm up, be watchful for low water pressure and air in the lines. Those are signs you’ve got an undetected leak somewhere.