How to Thaw Frozen Drain Pipes : Tips and Tricks


Plumbing How To

During cold winters with freezing temperatures, frozen water pipes or frozen drain pipes are always a risk. In this Plumbing How To we will show you that when the water inside your plumbing pipes freezes, the ice inside will start to expand and block the flow of water through the frozen pipes and it might even burst pipes.

When pipes inside your walls, in the attic, the basement or underneath your floors freeze, the ice inside will start to expand, if the ice expands enough it will cause the frozen pipes to burst and they will start to spill gallons of water. The leaking water in turn can cause up to thousands of dollars of damage to your home. The winter months can be detrimental to more than just your pipes, if you need the exterior of your home looked at contact Cincinnati roofing.

Prevent damage to frozen pipes

If you are able to locate the frozen pipes in time, you might be able to prevent the damage; but the frozen pipes must be thawed before any cracks appear. This article will show some ways to prevent frozen pipes so you won't need to find a local plumber.

Locations prone to frozen pipes

Depending on the structure of your home, there are a number of risky locations where water pipes are exposed to extreme temperatures more then on other locations inside your home. It is advisable to make sure the pipes are insulated with foam insulation wrap in those particular places.

Drain pipes most susceptible to freezing:

  • Located inside an outside wall of your home
  • Underneath a sink that's on an outside wall
  • In an unheated crawlspace, cellar or attic

Locating Frozen Pipes

To locate the frozen pipes and to determine which section of pipe is frozen, you can go about feeling the pipes with your hands.A frozen pipe will feel cold to the touch, pipes that still have water flowing through them will feel a lot warmer. An easier way to find frozen pipes is to use an infrared thermometer.

Frozen main line

When you have no water comming from any of the faucets in your home, then it could be that the water main line is frozen. Usualy the frozen section of the main line is in between the water meter and the main line's entrance point to your home. The main line should be buried at your locally mandatory depth to avoid the main line from freezing.

Frozen water pipes

When you have no water comming from only one faucet or in only a certain part of your home, then you should probably look for the the frozen water pipe inside the outside walls, your basement or in the attic. To prevent some freezing you can open all bathroom and kitchen sink cabinets to allow more warm air from your home to warm the pipes.

Thawing a frozen main or frozen water pipes

If your pipes are frozen, but you are lucky enough that the frozen pipes have not yet ruptured completely, then you will need to thaw the pipe! Depending on the location of the frozen pipes there are a couple of plumbing tools and techniques to go about finding the frozen pipe

  • Try the different faucets in your home to identify the frozen pipe(s).
  • Trace the frozen pipe from the faucet to possible cold areas mentioned above.
  • The frozen pipes will often have an area that appears frosted.

Ways to Thaw a frozen pipe

Once you have located the frozen pipe, you are ready to start thawing the pipe. You can thaw frozen pipes using the various methods and "plumbing tools" described below.

Thawing frozen pipes with a hair dryer

An easy and safe way to thaw a pipe yourself is to use a (high power) hairdryer. Almost everyone has got a hair dryer available and there is almost no risk of fire.

  • Turn on the frozen faucet and remove all the ice from the system once the frozen blockage has been cleared.
  • Gradually warm the frozen section of pipe from the faucet towards the frozen core defrosting the pipe.

Thawing a frozen pipe with a portable heater

If you happen to have a portable electric heater, then you can use it to melt the blockage inside the pipe by directing the heater onto the frozen section of the pipe.

  • Open the frozen faucet to remove all the ice inside once the blockage has been defrosted.
  • Gradually heat the frozen pipe from the faucet towards the frozen core.

Thawing a frozen pipe with a heat lamp

For people with a either a infrared heat lamp or an incandescent heatlamp, you can use the lamp to heat the pipe by directing the heater onto the frozen pipe.

  • Open the affected faucet to remove all the ice inside the system once the frozen blockage has been eliminated.
  • Gradually heat the blocked pipe from the faucet towards the frozen core defrosting the pipe.

Thawing frozen pipes with electric heat tape

A slightly different method is the use of an electric heat tape. This professional piece of equipment is like a ribbon type wrapper that has heating elements inside it. It is wrapped around the frozen section of the pipe. The temperature is then controlled with a thermostat.


Propane torches and heat guns are dangerous and can cause fires, not to mention that a frozen pipe can crack or break if warmed too quickly.

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