What to Do If Your Pipes Freeze and How to Unfreeze Them

There’s no need to panic if those temps plummet

Water flowing into sink
Photo: Catherine Falls Commercial / Moment / Getty Images
Water flowing into sink
Photo: Catherine Falls Commercial / Moment / Getty Images
Jouviane Alexandre
Contributing Writer
Updated September 7, 2023

Highlights

  • Pipes can freeze when temperatures drop and they lack insulation.

  • Act quickly when pipes freeze to prevent bursts and water damage.

  • Signs include frost, leaks, slow faucets, bad smells, and loud noises.

  • Unfreezing pipes is possible if you carefully apply heat.

  • Call an emergency plumber right away if a pipe bursts.

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If the water in your home isn’t flowing out of the faucet during the winter months, your pipes may have frozen over. It can be challenging to keep pipes from freezing, especially if they aren’t properly insulated and are exposed to the elements. However, taking action quickly to combat this common wintertime problem can save you money and even prevent major damage to your home. Here’s what to do if pipes freeze, and how to prevent the situation from happening in the first place.

What Causes Pipes to Freeze? 

Despite winterizing your pipes before the first big chill, there’s a chance that they can still freeze. If the water inside a pipe freezes, it will expand, causing a pipe to burst.

The most common reasons a pipe will freeze are:

  • Temperatures drop below 20 degrees.

  • The pipe is exposed to the outdoor elements, like water sprinkler lines, outdoor hose bibs, and swimming pool supply lines.

  • The pipes supply water in cooler areas like crawl spaces, kitchen cabinets, garages, basements, and attics.

  • Pipes have no or very poor insulation.

Although it’s common for pipes to freeze in cooler climates, do not assume that your pipes are impervious if you live in the Southern U.S. or warmer climates. These areas can be much more susceptible to freeze damage, especially if your pipes are located outside. Taking extra precautions to winterize your pipes can help avoid frozen pipes when the forecast calls for temperatures below freezing. If you find yourself with a frozen pipe, here are a few tips to get your water flowing again.

What to Do If Your Frozen Water Pipes Burst

If your pipe has already burst, it’s best to turn off your water supply and call an emergency plumber near you ASAP. If the situation is milder and your pipe hasn’t already burst, you can follow any of the below methods.

How to Temporarily Repair a Cracked Pipe

If your entire neighborhood just got hit with a snowstorm, it’s likely many of your local plumbers’ phones are ringing off the hook. If it will be a few days before a professional can arrive to fix a pipe, you can attempt to temporarily repair a small pipe with a patch or clamp until an expert comes. 

To repair a small hole in a pipe, you will either need to patch or clamp it (depending on the severity of the damage). Here is how you determine which course of action to take:

DamageTemporarily Repair
A regular pinhole leakClamp or patch
A leak near or at the jointPatch
A leak with obvious corrosion nearbyCut and replace the pipe

How to Find the Frozen Pipe

Chances are you were alerted to a frozen pipe thanks to a slow-dripping faucet, but other times, the source may not be so clear. Here are some other signs for how to tell if your pipes are frozen:

  • Frost appearing around the outside of a pipe

  • A pipe that is misshapen, cracked, or bulging in certain areas

  • A bad smell coming out of the faucet from backed up water

  • No water (or a very slow trickle) when using a faucet

  • Dampness or signs of water damage around walls or ceilings

  • Whistling and/or banging sounds coming from pipes

Once you know which faucets are affected, follow the line from each and touch the pipes to feel for the coldest areas. These spots will most likely be where the blockage is in the pipe. It’s possible that if there’s a blockage in one pipe, others are blocked with ice as well, so keep searching even once you find one spot. In more severe cases, you can also find the frozen area by following the pipe until you come across a spot that appears swollen or has a rupture in the sidewall.

How to Unfreeze Pipes

If the weather outside drops below freezing and you suddenly find that water won't flow from one of your faucets or fixtures, it's likely due to a frozen pipe. When pipes freeze, it's a matter of time until they burst. Quickly take the following steps to solve the problem and protect your home. These can apply to frozen PEX pipes, copper pipes, steel pipes, or any plumbing type.

1. Shut Off the Water Supply

In case of an emergency, such as a pipe bursting, it’s important to shut off the main water supply. Depending on your location and the type of house you live in, the main shut-off valve could be in the utility room, crawl space, basement, or meter. Painting the valve a bright fluorescent color can help you to find it quickly. 

Tagging the valve with your plumber’s contact information can also help to eliminate the stress of finding a local plumber in case of an emergency. If you're unable to find the main water supply valve in your home, call your utility company's emergency line for assistance.

2. Locate the Frozen Pipe

With the water shut off, try to find which pipe in your home is frozen. Check the pipes in your basement, crawl space, and attic. You should also check any exterior pipes and those inside cabinets, such as the ones under your sink. You'll know a pipe is frozen if it has frost on the outside.

3. Open Any Connected Faucets

By opening the faucets connected to your frozen pipe, you'll relieve pressure on any non-frozen portions. This will give you more time before the pipe bursts.

4. Check for Leaks

If there is water leaking from a crack in any part of the pipe, it has already burst. At this point, you should call an emergency plumber right away.

5. Attempt to Thaw

If you’ve found the pipe, it's easily accessible, and there are no visible leaks, you can take steps to try and thaw it out and prevent a burst. Use the tips in the section below to do so.

How to Thaw a Frozen Pipe

If the pipe only appears frozen, you can attempt to thaw it, but do not try to do so with a torch or open flame. This method could make the problem worse and potentially lead to a house fire or even cause the pipe to burst. You should also avoid pouring boiling water down the drain pipe or on top of the frozen pipes for similar reasons.

If you’ve located the frozen pipe and want to thaw it, follow these steps:

  • Keep the faucet for the pipe open so thawed water can drain.

  • Apply heat to the frozen area of the pipe using a hand-held hair dryer on its lowest setting. You can also try using a portable space heater (with care and as long as it’s not near anything flammable), wrapping an electric heating pad around the pipe, or wrapping the pipe with towels that you've soaked in hot water.

  • Apply heat until you see full water pressure return to the faucet.

No matter the defrosting device you decide to use, make sure to watch where the ice melts to avoid standing water and the risk of electrocution. If you notice any leaks in the line after you thaw out the frozen area, be ready to cut off the main water supply and call a professional plumber.

How Much Does It Cost to Fix Frozen Pipes?

Burst pipes will need to be replaced and a plumber is best equipped to handle the job. The average hourly plumber rate is around $330, depending on where you live and the size of your job.

As long as your frozen pipes haven't burst, a plumber will likely charge a flat fee of around $100 to thaw them out. However, the cost to repair burst pipes tends to be much higher and will ultimately depend on the extent of the damage. Expect to pay $500 on average, which includes the diagnosis and the repair itself.

Repairs may cost much less if there is only damage in a very small area, with costs as low as $150. On the high end of the range, some pay up to $5,000 to have new pipes installed underground and to mitigate water damage caused by flooding from the burst. A mainline pipe burst costs an average of $1,100 to repair.

Preventing Frozen Pipes in the Future

After your pipes are repaired and back in working order, you should take steps to prevent freezing in the future. You should also know how to keep pipes from freezing when you’re out of town. If you call a plumber to help fix the issue, they’ll also suggest what repairs or improvements you should make (and may even make those improvements in the same visit).

Below are the top tips for preventing frozen pipes:

  • Having proper pipe insulation to prevent freezing in unheated spaces like attics, crawl spaces, and basements.

  • Sealing cracks in walls to keep cold air out.

  • Insulating your pipes.

  • Always keeping your home heated to 55 degrees or more, even when away on vacation.

  • During spurts of severe cold weather, open your under-sink cabinets to keep heated air circulating and keep faucets slightly open to keep water running through.

  • Winterizing outdoor faucets by removing hoses, insulating them, and shutting off your outdoor water supply.

DIY vs. Hiring a Pro

Unfreezing a frozen pipe requires some nuance and a great deal of patience. Fortunately, it's a possible DIY project even for beginners; however, it doesn’t always work.

Frozen pipes are dangerous and can lead to further damage down the road if they go unfixed. When water freezes in your pipes, it expands and makes your pipes burst or break. In addition to the cost of replacing your pipes, this can cause up to thousands of dollars worth of water damage. 

If you suspect frozen pipes and you weren’t able to thaw them on your own, turn off your water supply and hire a plumber as soon as possible. Your plumber's cost will undoubtedly be less than the cost of repairs. There’s no telling when your pipe will burst. A plumber can properly thaw your pipes and give you tips on how to keep your pipes from freezing and causing an emergency in the future. Their liability insurance is an added bonus as it should help cover any mishaps that happen during repairs.

Ebonee Williams contributed to this piece.

Frequently Asked Questions

Thawing a pipe yourself usually takes around 30 minutes but can take longer depending on outside weather conditions, how long the pipe has been frozen, and its location. If you’ve been trying to unfreeze a pipe yourself for over an hour with no solution, it’s best to call a plumber.

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Learn more about our contributor
Jouviane Alexandre
Contributing Writer
Jouviane has spent eight years covering home and lifestyle, focused primarily on DIY and remodeling. When she isn’t working, she’s busy researching DIY projects to update her 123-year-old Colonial-inspired house.
Jouviane has spent eight years covering home and lifestyle, focused primarily on DIY and remodeling. When she isn’t working, she’s busy researching DIY projects to update her 123-year-old Colonial-inspired house.
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