Are you here because you’re taking a relaxing shower, but all of a sudden you heard a gurgling toilet sound? I am sure that sound must have made you question your life choices. If not, at least, it disturbed you enough that it took you here searching for “Why is my toilet bubbling when the shower is running?”

Now you are here thinking: Ugh, how peaceful your life was, but now you have to read this whole blog to understand why your toilet was gurgling when the shower was running. After all, you don’t want to ruin your next shower experience.

I promise I’ll try to make it as much less boring as possible. Plus, I’ll answer your main question “Why is my toilet bubbling when the shower is running?”. Not only that, I’ll also help you in fixing this toilet bubbling problem before it turns into a bigger problem.

Let me first calm you down with my comforting words:

• Your toilet is not haunted!
• Your plumbing system is not plotting against you!
• It just means something is wrong inside your pipes. 
• You’re not alone in this! Many people face the same problem!

Let’s break the topic down to make it easier for you to understand it.

What Does It Mean When Your Toilet Bubbles?

When your toilet bubbles, it basically means your plumbing system is screaming for help. You’ll either see air bubbles in the toilet water or hear disturbing ‘glub-glub’ noises. If you have seen the bubbles or heard the weird noises, don’t ignore them. They indicate that something’s blocking the proper flow of water and air in your pipes.

The Connection Between Your Toilet and Shower

Your shower and toilet aren’t just close to each other; they share the same drain line. You can think of this line as a highway. When there’s a traffic jam in one lane, it definitely affects the other lanes in some way.

• So, when you shower, water rushes down the drain and displaces some air. 
• Usually what happens is that air escapes through plumbing system ventilation (a.k.a. vent pipes).
• But if something’s clogged, that air has nowhere to go, but to back up through your toilet.

That’s why you see bubbles. 

The Role of Air Vents in Plumbing Systems

To keep things flowing smoothly, your plumbing relies on Air vents. These vents let air move freely, preventing negative air pressure in pipes.

If an air vent gets blocked, your drains get confused. So, you start hearing gurgling toilet sounds. In other words, your toilet starts acting up.

Common Causes of Toilet Bubbling When the Shower Is Running

So, what’s causing this bathroom rebellion? Here are the usual suspects for you:

• Clogged Drain Pipes: Things that cause a drain line blockage are: Hair, soap scum, and other debris. They disrupt the water flow.
• Blocked Vent Pipes: The power of a clogged vent stack is that it can’t let air escape through it. So, it forces it through your toilet instead.
• Partial Blockages in the Drain Line: If there’s a wastewater flow restriction further down the line, you’ll get weird plumbing behavior in multiple fixtures.

How to Know a Clogged Vent Pipe Has Led to Bubbling Toilets

If a clogged vent pipe has caused the bubbling in your toilet, you’ll notice one or more of the following signs:

• Water drains slowly or gurgles in multiple fixtures.
• Your toilet water level fluctuates unexpectedly.
• You smell sewer gases near your drains. (Gross.)

Is Bubbling Dangerous for Your Toilet and Plumbing System?

You can think of ignoring bubbling toilets like ignoring smoke coming from your car. It’s only going to get worse with time, right?

• Clogs can grow, leading to full sewer line clogs.
• Pipes can crack from pressure build-up.
• You could end up with raw sewage in your bathroom. (Not the renovation you wanted.)

You might have realized by now that fixing the problem early saves you money, time, and a whole lot of stress. Doesn’t it?

Steps You Can Take to Fix Bubbling Toilets

Try these DIY fixes before calling a pro:

• Check for Visible Clogs: Well, don’t just check, but also try removing soap scum, hair, and debris from your shower drain and slow-draining toilet.
• Inspect the Vent Pipe: Find and remove nests, leaves, or ice blocking especially the vent stack on your roof. The vent stack is a vertical pipe that connects the drainage system and exits at the roof level.
• Snake the Drain Line: Be brave and use a plumber’s snake to break up drain line blockages; I know you can do it.
• Clear the Shower Drain: This time, you don’t have to deal with the visible clogs. How will you clear the drain then? Just pour boiling water or a baking soda-vinegar solution to dissolve any buildup.

When to Call a Professional Plumber

If you’re tired of trying all these fixes but your toilet is still bubbling, it’s time to call a pro. 

If you don’t agree with that, there are some signs that indicate you need expert help, such as:

• Water is backing up into multiple drains.
• The bubbling gets worse over time.
• You suspect a main sewer line obstruction.

Conclusion

Now, you know very well your toilet is bubbling when the shower is running because something’s clogging your plumbing system. It doesn’t matter if it is a clogged vent stack, sewer line clog, or some other blocked component of your plumbing system; do not worry. All of them can be dealt with. Let me tell you again these issues can cause real damage if something is not done about them at the right time.

I would say: don’t wait until your shower turns into a swamp. Do something about it right now!

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