Can A Bathtub Drain Freeze? (We Have The Answer)

Ossiana Tepfenhart
by Ossiana Tepfenhart

About two years ago, there was a major snowstorm in my area. Our heater at the time didn’t work, and the insulation in our building sucked. This led to indoor temperatures as low as 25 degrees until we got it fixed. At one point, I began to worry about taking a bath. What could happen? Could a drain actually freeze and cause a backup?

Bathtub drains commonly freeze during the colder months if there is no insulation around your pipes, or if there is standing water anywhere throughout. Find the furthest faucet from your water heater, and turn the cold water on so it barely drips. This will keep the water flowing and prevent the pipes from freezing.

A frozen bathtub drain is no laughing matter, and not just because it could ruin your chances at a hot bath. Before you run the risk of having this happen to you, you should learn about what you should know if you’re running the risk of a frozen drain.

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Is It Possible For A Shower Drain To Freeze?

Believe it or not, it’s possible for a bathtub drain or a shower drain to freeze. When this happens, it’s actually a pipe that connects to your drain that freezes, rather than the actual drain itself. If the clog is fairly large, it can cause the pipe to start leaking. With that said, it’s something that you can easily fix.

There are many parts of American where having a frozen shower drain is just a part of life. For example, people who live in Minnesota, Alaska, and North Dakota often struggle with keeping their plumbing thawed out during the colder winter months. If you never had this happen before, consider yourself lucky.

How Can You Tell If Your Bathtub Drain Froze?

Most of the time, it’s a matter of circumstances. If all the following are currently true, you probably have a frozen drainpipe:

  • It’s below 32 degrees Fahrenheit outside. Your bathtub drain won’t freeze in warm weather, so it’s safe to say that this is a cold-weather issue.
  • Your bathtub or shower isn’t draining, despite you having the drain on. This is a sign that you have a clog, at the very least. Whether the clog is due to a frozen pipe or just excess hair remains to be seen.
  • You’re certain there are no hair blockages. If you recently snaked your drain, then you shouldn’t have a clog.
  • There’s little to no insulation around your drain pipe. Homes have insulation to protect pipes, people, and property from being exposed to the elements. If you don’t have much insulation around your bathtub drain, the chances of you having a frozen drain skyrocket.

Is A Frozen Shower Drain Pipe A Major Problem?

If your shower drainpipe can’t be unclogged through normal methods, then it can be a major issue for you. Freezing can cause a pipe to burst if left unchecked. However, you shouldn’t let this be a cause for panic. This just simply means that you will have to thaw out your pipe, and that you’ll have a harder time taking a bath until the piping in your home thaws out.

What Causes A Bathtub Drain Pipe To Freeze?

The root cause is that there’s a portion of your drain that is exposed to temperatures cold enough to cause freezing, and that there’s enough water in a certain part of your drain to cause it to pool and freeze up. More specifically, this tends to happen for one of the following reasons:

  • The piping has been exposed to freezing temperatures outside. This is the most common cause these days, particularly near coastal areas.
  • The piping goes through an unheated or uninsulated part of your home. This could be a crawlspace, a basement, or even an attic that is just too chilly.
  • There’s a continuous drip of cold water in the pipe. This can happen due to a toilet that’s continuously dribbling in, or because of a sink that has a faucet that’s stuck on a steady drip.
  • There’s water that has pooled up in one part of your drain. If your drain has a portion that dips down, this may be the reason why you’re experiencing difficulties.

How To Unclog A Frozen Bathtub Drain

The bad news about having a frozen tub drain is that it can cut your bathing time short due to the clog. There’s some good news when it comes to having a frozen bathtub drain, too. This can be fixed fairly easily. Here’s how to do it:

  • Boil some water and add salt. A cup of salt for three cups of water should do the trick. Don’t worry about the type of salt that you’re using. Cheap table salt is perfectly fine for this.
  • Pour some baking soda and vinegar down your drain. This will set off a chemical reaction that will clear out your pipes, heat things up, and break the ice.
  • Pour the boiling saltwater down the drain. This will loosen up everything. The salt will also help break down the ice, much like it would if it was poured on a sidewalk.
  • Follow the water with a hot water rinse from your shower or tub. Just leaving your shower on high for 5 minutes should clear up any remaining frost that’s clinging to your pipe.

Is A Frozen Bathtub Drain Preventable?

Frozen bathtub drains are preventable in many cases. You just need more insulation around your plumbing and in the homes of your walls. This will help improve the overall temperature of your home and keep the pipes at a temperature that won’t lead to freezing. Of course, to make sure that you don’t get a frozen drain, you also need to keep your home above freezing temperatures.

It’s important to realize that there will be moments where a frozen drainpipe is not really that preventable. For example, if you live in an area that is known for having frigid temperatures, there will always be a chance that your pipes will freeze. This is because we can’t always control the temperature of the pipes outside of your home.

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Related Question

Can you use Drano to get rid of a drain clog caused by a frozen shower pipe?

While this solution has been mentioned online repeatedly, the truth is that it’s not a good idea. Drano is a highly caustic chemical that can easily cause damage to your piping, clog or not.

Can you use an open flame to get rid of a drain clog caused by a frozen drainpipe?

Heat should be a way to fix a drain clog, but this is not the way you want to go about it. An open flame can damage your drains and potentially even cause your drain to tear a hold in itself. If you insist on using direct heat, crack some heating pads and place them on your drain.

How long does it take a pipe to freeze and burst?

You usually will have to have the pipe exposed to temperatures below 20 degrees Fahrenheit for a total of six consecutive hours before you run the risk of having a burst pipe. With that said, the colder the temperature, the more likely it is that you will have a burst pipe sooner rather than later.

Ossiana Tepfenhart
Ossiana Tepfenhart

Ossiana Tepfenhart is an expert writer, focusing on interior design and general home tips. Writing is her life, and it's what she does best. Her interests include art and real estate investments.

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