Why Is My Toilet Bubbling/Gurgling?

So, you’re enjoying your morning shower when all of a sudden you hear a bubbling noise from your toilet.

What the heck?

Here are some possible causes:

Let’s explore each of these issues and how you can fix them.

Cause #1) Clogged sewer drain line

Check out this image:

Source: Cornell University

See that drain pipe in the bottom left? If there’s a clog there, water will back up into the lowest drain, in this case that drains your toilet. That backing up of water is causing the bubbling/gurgling noise.

Causes of a clogged sewer drain line include:

  • Tree roots (trees planted over the drain line love to invade nutrient-rich drain lines with their roots)
  • Debris
  • Odd items flushed down the toilet

How to fix a clogged drain line

Unclogging a drain line depends on what’s causing the clog and how far down the clog is.But you can try a few things before calling a professional plumber:

  • Use a plumber’s snake (also called an auger) on your toilet drain. If this does not work, the clog may be too far down the drain line.
  • Use a plumber's snake at the sewer clean out. To find the sewer cleanout, look around the sides of your home. You may not have a sewer line cleanout if your home was built before 1978.

If none of these worked (or you don’t want to do them yourself), you’ll need to call a plumber for help.

Cause #2) Blocked vent stack

The vent stack is a pipe that rises from your plumbing system and out through your roof. Its job? To keep nasty sewer gas from backing up into your home and helps water in your plumbing flow smoothly.

Again, this image tells the story:

Think of this vent stack as a straw in a glass of water. As long as the top of the straw is clear, water flows freely.

But what happens If you put your thumb over the top of the straw and take it out of the water? The water stays in the straw and does not flow. It’s like magic. But not really.

Anyway, if the vent stack is blocked by, let’s say, a bird’s nest, water in your plumbing won’t flow freely and air will back up into your plumbing. That air will try to escape somewhere (In this case, your toilet).

How to fix a vent stack

If you’re feeling brave, get a ladder and head up to your roof to see if the plumbing vent is obstructed.

Plumbing stack vents are usually black plastic ABS or lead pipe and look like this:

Cause #3) Blocked toilet trap

The toilet trap is a curved section of the toilet's drain pipe that retains a small amount of water to prevent sewer gases from entering your home. If the trap becomes blocked by an object or excessive waste, it can cause air bubbles to appear when you flush.

How to fix a blocked toilet trap

  1. Plunge the toilet: Start by using a plunger. Ensure that there is enough water in the bowl to cover the suction cup of the plunger. Place the plunger over the drain opening at the bottom of the toilet bowl and push down firmly, then pull up quickly. Repeat this plunging motion several times to create pressure and dislodge the blockage. If the blockage is severe, you may need to repeat the process multiple times.

  2. Use a toilet auger: If plunging doesn't resolve the issue, you can try using a toilet auger. Insert the auger's flexible cable into the toilet drain and slowly rotate the handle while applying gentle pressure. This can help break up and remove any stubborn clogs in the trap.

  3. Call a plumber: If the blockage persists or the toilet trap cannot be cleared with these methods, it's recommended to contact a licensed plumber. They have specialized tools and expertise to handle more complex clogs and ensure that the toilet trap is thoroughly cleared without causing further damage.


Need a Florida plumber?

Need help diagnosing this plumbing problem and want it fixed ASAP? Contact Plumbing Today for a plumbing repair.

Plumbing Today provides award-winning plumbing services and has locations in Sarasota, Tampa Bay, Orlando, Naples and serves the surrounding areas in Florida. If you have any questions, talk to one of our expert plumbers for help!

Posted in: Troubleshooting

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