How to Defrost Frozen Pipes

Frozen pipes can be a huge inconvenience and can cause water damage if they burst…Unfortunately for Houston, our homes are not designed to withstand hard freezes, and we typically experience a pipe-breaking freeze once a year.

In the situation where your pipe is frozen but not ruptured, you need to promptly thaw it out. Below are a few techniques to get the pipes defrosted and water flowing again:

NOTE: Never use a flame torch because of the fire hazard it creates. Open flames (of any kind) are a very dangerous way of defrosting your pipe and can cause a house fire.

Pipe Thawing

A pipe is most likely  frozen if you turn the faucet on and no water comes out or just trickles. As soon as you realize a pipe is frozen you need to take immediate action.

  • Open the faucet supplied by the frozen pipe.
  • Identify the frozen water pipe and find the location of the stoppage.
  • Follow the pipe back from the faucet to where it runs through cold areas such as an exterior wall or unheated attic space.
  • Often the frozen area of the pipe will be frosted or have ice on it. If the situation is getting critical the pipe may be slightly bulged or look slightly fissured.

NOTE: if  the pipe bursts before it is thawed, then shut off the water to your home immediately!

Frozen Pipe in the Wall

When you find that the frozen pipe serving the faucet is behind a wall or ceiling, you’ve got a challenge on your hands. You may try these two options.

  • Turn up the heat in the house and wait;
  • Tear out the wall or ceiling section to get at the frozen section of pipe. Then thaw the pipe as an exposed pipe;

Exposed Frozen Pipe

If the frozen pipe is exposed (in the attic, under a sink or even outdoors), then you have several options to defrost the pipe.

When working on thawing the pipe leave the main water valve open (near your water meter) and remember to heat the pipe from the faucet toward the frozen area. This way, the water can flow out as the ice melts and the water pressure in the pipe will force the ice out once it melts sufficiently.

Techniques for Thawing an Exposed Frozen Pipe

Hair Dryer
One of the best and safest ways to thaw the pipe is to heat the area with a high power hair dryer. Make sure to open the faucet and then heat the pipe working back from the faucet toward the frozen blockage.

Heat Lamp
A heat lamp works well to heat an exposed pipe. You can use an infrared or incandescent heat lamp. Be carefully when aiming the heat towards a wall or any flammable material (drapes, wallpaper, paper product under a sink) – these could be a fire hazard. Again, Make sure to open the faucet and then heat the pipe working back from the faucet toward the frozen blockage.

Small Portable Heater
If you have one of those small fan heaters they work great when warming pipes under a kitchen or bathroom cabinet. Direct the heater onto the frozen section of pipe. Again, be carefully when aiming the heat towards a wall or any flammable material (drapes, wallpaper, paper product under a sink) – these could be a fire hazard. Do not leave unattended. Also, Make sure to open the faucet and then heat the pipe working back from the faucet toward the frozen blockage.