How to Thaw Frozen Pipes: Defrosting Techniques That Work


Hardly any problem around the house scares a homeowner like a frozen pipe: The pressure caused by freezing water can damage even the strongest pipes. Once the frozen pipe bursts, it becomes a ticking time bomb: As the pipe thaws, up to 8 gallons of water per minute will flow into your home, likely causing thousands of dollars in damage.

Although hiring a professional plumber is the best option to deal with this problem, we don't always have the time (or money) to hire a plumber. No panic! You can solve this problem yourself by following the steps below to thaw frozen pipes.

Tools and materials

Project overview

working hours: 1 hour
total time: 1 hour
Skill level: Beginner
Estimated costs: $0 to $35

before you start

It is absolutely important that you locate and turn off the water at the main shutoff valve in your home before beginning the defrost process. If a pipe freezes, there's a good chance the expanding water will cause the pipe to burst. Once the water thaws, it flows freely and can potentially flood your home. If you don't know where your home's main water shutoff valve is, you can't stop it.

RELATED: Protect your pipes from freezing and save 20% on this top-rated heat cable

STEP 1: Find the frozen pipe.

How to Thaw Frozen Pipes - Woman Turns On SinkHow to Thaw Frozen Pipes - Woman Turns On Sink


Sometimes the most difficult part of this task is locating the frozen pipe. One way to get to the bottom of the problem is to open all the faucets in your home. If water isn't reaching a particular faucet, trace the lines leading away from the faucet. Every few feet, check the plumbing with your hands (a frozen pipe will literally feel ice cold) and continue until you find the affected area. If none of your faucets are flowing water, the problem may be with the main supply line. It is usually located in the basement or crawlspace on the side of the house that faces the street.

STEP 2: Shut off the water supply to the house.

How to thaw frozen pipes – Turn water valve by handHow to thaw frozen pipes – Turn water valve by hand


Once you locate the frozen pipe, go to the main water supply valve and turn it clockwise to the “off” position. Next, turn on the water at all sink and tub faucets in your home and drain any remaining water from the system. Flush your toilets too. Bring a bucket, a mop, and two or three towels that you wouldn't mind ruining in the place of the frozen pipe.

RELATED: Everything You Need to Know About Winterizing Pipes

STEP 3: Thaw the frozen pipe.

How to Thaw Frozen Pipes - Woman holding towel to pipeHow to Thaw Frozen Pipes - Woman holding towel to pipe


At this point, your mission is simple: heat the frozen pipe. The process is the same whether you are thawing metal, PVC, or PEX pipes. To defrost, homeowners typically use hair dryers, heat lamps, and heating pads. Low-tech solutions can be just as effective. For example, you can pour hot water over towels and place them over the frozen piece of pipe.

More important than your heat source is your technique: It's best to start heating at the edge of the frozen area, on the side closest to the nearest kitchen or bathroom. This allows the steam or water created by the heater to escape from the pipe. Continue heating, moving step by step along the frozen pipe. Alternatively, if you cannot provide heat directly to the frozen pipe, try installing a space heater in the nearest accessible area. If that's not possible, turn your thermostat up a few degrees. An increase in your electric bill would be small compared to a costly repair. Whatever method you use, work quickly but be patient. Depending on weather conditions, where the frozen pipe is located, and how long it has been frozen, it can take anywhere from 30 to 45 minutes for a frozen pipe to thaw.

STEP 4: Check the pipe for leaks.

How to Thaw Frozen Pipes - Person Repairs Leaking PipesHow to Thaw Frozen Pipes - Person Repairs Leaking Pipes


When you are sure the frozen food has melted, return to the main water supply valve and turn it partially on. Return to the pipe and check for leaks. If it bursts, turn off the power again, call the plumber, and get to work cleaning up. If the pipe appears to be directing water properly, turn on the water supply completely and close any faucets or spouts that are still open.

RELATED: Does homeowners insurance cover frozen pipes?

How to Thaw Frozen Pipes Outdoors

If the frozen pipes are on the outside of an RV or enclosed in a wall, you won't necessarily be able to thaw them with a space heater. Unless you're willing to wait for Mother Nature to help with warmer temperatures, you'll need to get creative and use one of the following methods.

How to Thaw Frozen Pipes in an RV

Some mobile homes have plumbing in an open crawlspace beneath the home, making them vulnerable to freezing in cold weather. Since it is impossible to warm the air around these pipes with a space heater, you must apply direct heat. You can use a regular blow dryer or a heat gun, like the ones you use to cure paint or epoxy. Turn the blow dryer to the maximum setting and hold it a few inches away from the frozen pipe to thaw it. If you use a heat gun, choose a medium temperature setting to avoid melting the PVC.

If you don't have a hairdryer handy, try using warm towels. Soak a towel in water, wring it out, then throw it in the microwave for 30 seconds. Wrap the hot towel around the frozen pipe to start the thawing process. Remember that the damp towel will not stay warm for long in cold temperatures. Therefore, plan to store a few on deck until you have successfully thawed the pipe.

How to thaw frozen pipes in a wall

If the frozen pipe is inside a wall and you have identified its location, you can thaw it using an infrared lamp. Position the lamp so that it directs heat toward the section of wall covering the frozen pipe. Make sure there is a distance of 60cm between the wall and the lamp to eliminate any risk of fire. Wait for the pipe to thaw. Keep in mind that if a pipe bursts, you may need to make a cut into the wall to make repairs.

How to Prevent Frozen Pipes

How to Thaw Frozen Pipes - Person Checks Water PipeHow to Thaw Frozen Pipes - Person Checks Water Pipe


To prevent a similar situation from occurring in the future, take steps to protect your vulnerable pipes. The average homeowner has several options available that do not require moving plumbing or changing the heating system.

  • Insulate your pipes. Cover pipes in the coldest areas of the home, such as the basement, crawl space, attic or garage, with pipe insulation.
  • Install heat cable. If you want to take it a step further, install heat tape, an electrical cable that you attach to pipes to warm them and prevent them from freezing in temperatures as low as 40 degrees below zero.
  • Open all your faucets and spouts until a trickle flows. Running water resists freezing better than standing water. If you open your hot and cold water faucets just a crack, the trickle of water will prevent your pipes from freezing.

Final thoughts

If you suspect a pipe is frozen in your home, you need to act quickly. If the pipe bursts, it could cause major flood damage to your home once it thaws, turning a relatively small repair into a major expense. Follow the steps above to locate and thaw the pipe so you can assess the damage and determine whether the pipe requires further repairs. If the pipe is actually damaged, you will need to hire a plumber to repair it.

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