How to Fix a Frozen Toilet Tank or Pipelines

If you live in a cold climate, you already know the agony of below-freezing temperatures and frozen pipes. Frozen pipes can happen throughout a house – from the laundry room to the kitchen and even the bathroom. When they happen, the sudden halt of water can put a damper on the most basic of needs.

One of the biggest hassles in cold weather is dealing with a frozen toilet tank or toilet pipeline. There are few things more frustrating and panic-inducing than not being able to go to the bathroom because your toilet won’t flush. It’s a time-sensitive situation that calls for an immediate fix, which is the purpose of this article. Read on to discover why your toilet tank or pipelines are freezing and what you can do about it to get things flowing normally again.

Toilet Won’t Flush In Cold Weather?

While a toilet that won’t flush due to a sudden drop in temperatures is a hassle, there is no reason to panic. You simply need to get a heat source on the frozen part to get the water moving again. 

The reason toilet tanks and toilet pipelines tend to freeze in especially cold weather is because of their proximity to the exterior of the home. If a toilet is situated on an outside wall, or its pipes run through an exterior wall, the toilet, and its pipelines are susceptible to freezing when the temperatures drop. This is because these areas are often not insulated well. If you know this is the case in your home, you can take steps to prevent the toilet or pipes from freezing, but if freezing has already taken place, you need to take action to prevent pipes from bursting or toilet hardware from cracking or leaking

Locating the Frozen Section of the Pipeline or Tank

Locating the frozen part of your home’s sewer system is probably the most difficult part of dealing with a frozen toilet. It isn’t always obvious where the blockage lies. Of course, if the freeze occurs in the toilet tank itself, you will likely be able to see that right away, but if the frozen part is in a pipe somewhere, it may be more difficult to find. This is especially true if you live in an apartment building where you may not have access to the water pipes in the building. 

Frozen Toilet Water Tank

Toilet tanks themselves rarely freeze, but the small water supply line that comes into the tank can freeze quickly if there is a sudden temperature drop and the toilet is situated on an exterior wall. In rare circumstances, porcelain toilets bowls, and tanks can crack due to the water expanding as it turns to ice during freezing.

Frozen Toilet Pipelines

When people talk about having a frozen toilet, they usually mean that there is a frozen blockage somewhere in the toilet’s pipelines. Toilets cannot flush without the flow of water, so when the pipes are frozen, no water can make its way into or out of them. This means the toilet will not flush and you must figure out where the frozen section is and thaw it out. Obvious signs of a frozen water pipe are condensation or frost on the outside of the pipes, they may be extremely cold to the touch, and they will sound solid when tapped with the handle of a screwdriver. Once you have found where the pipes have frozen, you can start thawing them out. 

6 Ways to Thaw A Frozen Toilet

The main thing you need to do to thaw a frozen toilet is to get a heat source on it. Depending on where the frozen section is, you have several options for doing this. 

1. Apply a Heating Pad or Cable

One of the best ways to thaw a frozen pipe is to wrap a pipe heating pad or heating cable around it. While this method takes time, it will reduce the risk of the pipe bursting because it thaws the frozen water slowly. Simply wrap a heating pad around the frozen section of pipe and turn it on to the lowest setting. You can purchase pipe heating cables here.

Pipe heating cable
Use a pipe heating cable

2. Drape Hot Towels

Lay down some old dry towels under the frozen section of the pipe to catch drips. Saturate some old clothes in hot water and lay them over the frozen pipes. This method will also take a little time and you will need to keep replacing the towels with new ones as the old ones cool off, but again, the slow thaw will help prevent burst pipes. 

3. Use A Hair Dryer

Another great option for thawing frozen toilet pipes is a hair dryer. With the dryer set to its low-heat setting, point it toward the frozen pipes closest to the toilet. Move the hair dryer back and forth as you work your way down the frozen pipe. 

4. Wrap Pipes With Heat Tape

Most home improvement stores carry heat tape. All you need to do is wrap a single layer of tape around the frozen section of the pipe, plug it in, and wait. Be sure to check the tape often to make sure it is working properly and not touching anything that might be flammable. 

5. Use a Space Heater

Using a space heater to thaw a frozen toilet works best if your bathroom is small. Position a space heater facing the frozen pipe and turn it on low. Make sure the heater is at least three feet away from any flammable surface or material and check it often to ensure it is operating safely. Never leave a space heater unattended or operating while you are sleeping. 

6. Pour Warm Water Into the Frozen Area

Depending on where the frozen part is occurring, you may be able to pour warm water over the frozen area to thaw it out quickly. This method works well if the tank or bowl themselves are frozen as the excess water will simply flow down the drain. Be sure to have dry towels under the area you are working in to catch any drips or spills while you are pouring the water. 

Preventing Frozen Toilet Pipes

Unfortunately, frozen toilet pipes may be the norm during the winter months where you live. If your toilet tank or pipelines freeze regularly, there are things you can do to prevent them from freezing the next time the temperatures drop below freezing in your neck of the woods. 

Insulate Pipes

If you know your toilet tank and pipelines are susceptible to freezing during the winter months, insulate them properly before the cold weather sets in. You can find pipe insulation and tape here on or in good home improvement stores. Alternatively, you can also wrap heat tape around them and plug them in when extreme temperatures threaten to freeze your pipes. 

Pipe insulation
Pipe insulation
Pipe tape
Pipe tape

Maintain Bathroom Heating

If your bathroom has at least one exterior wall, you need to make sure the heat in the room is sufficient to prevent the water pipes from freezing. This may mean installing a heat source in the ceiling or running a space heater during extremely cold days, but doing so will ensure you don’t have to deal with a frozen toilet during the winter. 

Winterize Your Toilet Water Tank and Bowl – Antifreeze

If you will not be using your home during the winter months or are planning to be away for an extended period during the cold season, you should winterize your home’s plumbing system. This begins with winterizing the toilet tank and bowl. 

First, turn off the water supply to the toilet tank by turning the water inlet valve clockwise as far as it will go. Flush the toilet. 

Remove the cover from the tank and hold the flush lever down until all the water drains from the tank. Next, get a bucket of water and pour it slowly into the bowl to encourage any remaining water to drain out. If any water remains in the bowl, sop it up with a sponge or dry cloth. 

Once all the water has drained away, add antifreeze to the toilet tank. Be sure to use an antifreeze that is rated for plumbing systems. 

Once your toilet is ready for the winter months, winterize the rest of your home by turning off the main water supply to the house, turning on all the taps to drain the water, and using an air compressor to blow out any remaining water from the pipeline.

Plumber and HVAC Technician | Website | + posts

As a retired Master Plumber Jamie has over 30 years of hands-on experience, making his plumbing knowledge second to none. He has also worked on both residential and commercial HVAC installation and repair projects.