What to Do When Your Toilet Bubbles When Your Tub Drains

There is nothing like the feeling of finishing up a shower. That blissful second when you turn off the spray and the swirling water in the tub drains away the last of your stress and worry of the day. Until it doesn’t.

The water suddenly backs up a bit, and you hear a distant gurgling sound. It turns out that the water in the toilet is gurgling and bubbling! As distressing as this might be, don’t give up on the bliss of the shower just yet – the solution is only a few words ahead.

What to Do When Your Toilet Is Gurgling When the Tub Drains

To Plunge or Not to Plunge

Whenever we have a problem with flushing or draining, our first inclination is to use a plunger, which is not a wrong move. Plunging is the first and the most obvious solution to a bathroom problem. We even have a whole article dedicated to finding the right plunger for your specific bathroom needs.

Indeed, plunging into the toilet is typically the first course of action. If you’re willing to try, make sure you don’t thrust too hard and observe whether the quality of your flush changes after your plunge.

With bubbling, however, the problem is usually a bit bigger than what our trusted plunger can solve. This is because of the way the draining works in our bathrooms. Before we discuss possible solutions, it’s important to know exactly how our toilet flushes and drains.

Why Does My Toilet Bubble When the Tub Drains?

There is more to the flushing system than meets the eye. The sink, the shower, and the toilet are all connected to the same drain pipe. When you get a clog in the main pipe, it will significantly affect the water drainage quality in all three drains.

When the drain gets clogged, the water starts backing up and filling the connecting pipes too. This traps the air at the other end and forces it to come out of the nearest exit path, which just happens to be your toilet. That’s why each flush results in more gurgling and bubbling.

Now that you know why this happens, let’s try to solve the problem!

Identifying the Cause of Bubbling in Your Toilet

It’s important to identify exactly when the toilet makes this bubbling because the solution may depend on the cause behind it. Here are a few questions you can ask yourself to identify the cause behind your toilet bubbling up when the tub drains:

  • Does the bubbling happen after you flush?
  • Does the bubbling happen as the sink is draining?
  • Does the bubbling happen as the shower/tub is draining?
  • Do you notice a change in the speed and quality of draining?
  • Did plunging change anything?
  • Is the water clear?

Observing these things may help you estimate where the clog might be. For example, if the bubbling doesn’t happen after you use the sink and instead happens when you drain the tub, the clog might be where the shower drain meets the main pipeline. If you notice that the speed and quality of draining are gradually getting worse, then this might mean that the water is not getting around the clog, and you need to take action. It could also mean that the clog is closer to the pipes, so some extra plunging might actually be useful.

After making the necessary observations, you can move on to the second step – how to solve it.

Oh Blockage, Where Art Thou?

Okay, so the plunger didn’t work, your observations led to nothing, and the gurgling continues. You have good reason to believe there is a blockage somewhere, but you can’t put your finger on where it might be just yet. The blockage may be in the drain and/or the toilet line, but it might also be in the vent stack.

The vent stack is usually a vertical line located on your roof, which regulates the ventilation in your pipes. Remember the air that was trapped and made your toilet gurgle? That air should have come out of that air vent! Animals and leaves like to nest in these small places, so you need to make sure that the sewer line is clean.

Make sure that you keep your vents clean and do regular checkups to ensure that your ventilation happens smoothly. There are numerous step-by-step videos and blog posts out there that show you how these vents can be kept clean. Here is a useful blog that explains how a clogged vent can be cleaned and how that helps with flushing.

The Toilet Keeps Gurgling: It’s Time to Call a Plumber!

If you’ve checked the vent and plunging doesn’t help, there is not much you can do. Enlisting the help of a professional is much better than resorting to DIY solutions that might leave you in even worse, not to mention stinkier, situations.

The plumber will come in with a cable-looking device called a snake, which has a camera and is used to identify what causes the blockage in the pipes and whether the problem lies in the vent or the drain. When they locate the source of the clog, the plumber can work to eliminate it directly. Here is a video that shows how plumbers get rid of a clog in a vent using a snake camera.

Asking the help of a professional will help you avoid unnecessary remodeling. They will save you time and money, so never hesitate to ask for their help!

The Bottom Line (Pun Intended)

Calling in a professional is critical in order to avoid any further damage. The problem at hand might be even bigger than a basic clogged drain or a damaged vent. There might be a clog in the sewer system that collects the waste of the entire neighborhood, not just your own.

In this case, it’s the municipality’s responsibility to take care of this problem. You can contact your neighbors to see whether they are also experiencing similar problems and contact local authorities and petition them to fix it.

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