Why Is My Toilet Bubbling?

Your house is a lot like a human body: when something goes wrong, it will show you signs. However, figuring out what those signs are pointing to can be the hard part. One such sign is your toilet bubbling up, especially when draining the bathtub, taking a shower, or running a nearby washing machine. While this might seem like a fairly small or mundane quirk, it actually could be telling you about an issue that you should try to get resolved fairly quickly. Check out this blog to learn more about what problems your toilet might be telling you about.

What Causes the Bubbles?

Toilet bubbling is usually caused by a phenomenon knowns as “wet venting.” According to plumbing codes, all drains are required to be vented separately to reduce pressure build up and vent sewer gasses outside. To make sure these vents don’t block up, each drain must be vented separately, however several drains in close proximity, such as in a bathroom, can all be connected to the same vent. When this is the case, a blockage in the vent can cause pressure to build up and air to enter and exit through a different fixture when you use one.

In other words, your toilet bubbling up when you drain the shower is a sign that you have a blockage somewhere in your vent pipe. However, that’s the easy part. Determining where the blockage lies is slightly more difficult. Here are some tips you can follow to try to remove the clog.

Clear the Shower Drain: Remove the strainer and push a plumbing snake down into the drain to remove any obstructions that are a foot or two down. Hair and soap scum from your shower or bathtub can cause clogs that could affect your entire bathroom. Once you’ve done this, fill the tub with a few inches of water and then drain it. If the problem persists, try the next step.

Clean Further Down: Try plunging your toilet. A clog in this line could still lead to wet venting when you drain the tub. However, if that doesn’t work, you may need to go further down your tub’s drain line. When this is the case, use an enzyme-based drain cleaner, baking soda, or peroxide. These won’t harm your pipes like harsh drain cleaners that you can buy from hardware stores.

Clear the vent: If neither of these first two attempts have worked, then you may need to clear out the vent itself. The main vent stack will be located on your roof. If you notice that leaves, dirt, and other debris have blocked your vent, clear it out. Then spray water down the vent pipe itself to clear obstructions further down. You may also want to use an auger to remove any stubborn clogs.