What to Do if the Toilet Bubbles When Flushed? Symptoms, Causes, and Fixes

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You go to the toilet and see the water in the toilet bowl gurgling. This is not normal behavior for a toilet and could mean trouble. There could be a number of reasons why your toilet is bubbling when flushed, some of which could be serious while other issues can be easily corrected.

In this blog post, we will look at the symptoms of a bubbling or gurgling toilet and the main causes but the blog would not be complete without covering how to fix the issue.

Why Do I Have A Gurgling Toilet?

There are a number of reasons why your toilet is bubbling but generally speaking, it is the negative air pressure in the pipes causing that awful sound and gurgling.

When the drain pipes become blocked, there is a build-up of air pressure due to blocked air. If the air in the pipes is unable to flow freely it will start to suck and push trying to get free which is why bubbles start to appear in your toilet.

A properly functioning toilet will have a stable air pressure allowing the waste, water, and air to flow without causing any issues.

It is very important to note that when your toilet starts to gurgle and bubble it is a sign of much bigger problems.

Symptoms Or Signs Of A Gurgling/Bubbling Toilet

Before attempting to fix a toilet that is bubbling or gurgling when flushed, ensure that the issue is only with the toilet and not the home’s drainage system as a whole.

Some of the indicators to be on the lookout for include:

Bathtub Or Sink Drain Gurgles When Toilet Is Flushed

Once a toilet is flushed the water and waste normally flow down the drain pipe displacing the air however if the pipes are clogged the air will have to find a different path which in this instance is the bathtub drain making this bubbling noise.

Toilet Bubbles When Bathtub Drains

All the plumbing in your house is interconnected to the main drain pipe which then leads to the sewer. If you hear your toilet gurgling or bubbling while draining a bathtub, this indicates that there is a blockage in the main drain. This is easily tested by turning the faucet on in your bathtub and watching for bubbles. Conversely, if you do not see any gurgling or bubbling then the toilet drain is most likely the problem.

Toilet on a Septic Bubbles When Flushed

If your toilet is connected to a septic tank and it bubbles when you flush it then there could be a couple of reasons.

Firstly, the pipe that leads to the septic could be blocked which can be easily cleared by yourself or a plumber.

Secondly, your septic tank could be full which will need emptying to resolve the issue.

Water Backing Up From The Drains

Once there is a blockage in the drainage system you may find that water in your bathtub is backing up from the drain. This water is finding the only escape route as the drain is blocked. 

This is typically a later stage in the development of the blockage and should not be ignored.

Foul Smelling Bathroom

If your bathroom is smelling then it could mean that your drain is blocked and the air is unable to escape out and is being pushed back in through the open drains. 

You will need to search for the issue but a blocked vent pipe may also be contributing to the smell.

Causes Of Bubbling/Gurgling Toilets

Whether it’s a blocked toilet or a septic tank that needs emptying these issues need to be resolved as soon as possible. It is important to know what the cause of the problem is so that you can make a plan to fix it. That could be you fixing it yourself or hiring a professional to do the job.

Toilet Clogged

Gurgling and bubbling toilets are early signs that your toilet may be blocked. The main causes are excess waste or foreign objects flushed down the toilet such as feminine products and wet wipes.

Needless to say that the clog will have to be sorted quickly otherwise it can lead to further issues.

Blocked Vent Pipes

A vent pipe also known as a vent stack is a vertical pipe that sticks out of your roof regulating the air pressure in your plumbing system while also releasing any exhaust gases. This vent may get blocked in time by dirt or a build-up of flying leaves or any multitude of ways.

Typically your bathroom will start to smell while the bubbling is going on which is a good indication that the vent pipes are blocked.

Residue Build-up In The Toilet

If you live in an area where there is hard water then this could potentially be a problem. Hard water contains trace elements such as calcium, magnesium, and iron. These can calcify over time and the build-up can block the drain pipes, causing bubbles when flushed.

Main Line Clogged

If you flush one toilet in your home and the other toilet gurgles or bubbles then this is a surefire sign that the clog is in the mainline. This can be caused by a blockage by tampons being stuck which can absorb water and increase to 10 times their size or something else that is not allowing the waste to flow.

Camera Scope Of Drain Pipes

If you have tried to find the problem but are still not sure where the blockage is, then hire a plumber to do a camera scope of the drain pipes. This will involve the plumber inserting a tube with a camera on the end through your entire plumbing system, revealing where the block is and in some cases cleaning it immediately depending on the blockage.

How To Fix A Gurgling/Bubbling Toilet

Fortunately, the toilet bubbling or gurgling is an easy fix and can be handled by yourself, in most cases anyway. However, you may come across certain situations that will require the help of a professional plumber.

Below are a few things that you should do yourself before picking up that phone and spending your hard-earned money on a plumber.

Deep-Clean the Commode

If after checking you realize that the bubbling is due to a blockage in the toilet bowl bought on by hard water mineral build-up then it is time to get it cleaned up.

Naturally, the toilet gets used a lot during the day but very rarely does it get the proper attention when it comes to cleaning it.

Turn the water off by turning the shut-off valve and emptying the water out of the toilet bowl with a small cup. Pour distilled vinegar into the toilet bowl and leave it to sit for about an hour. Using a green scarab, take some baking soda and scrub the toilet bowl removing any build-up. Turn the water back on and flush the toilet if the toilet is still bubbling then it could be a blocked pipe or blocked vent.

Time To Plunge

A plunger is your best friend when it comes to blockages in the toilet.

However, if your toilet is gurgling then you will need to first seal off the other drains such as your sink and bathtub so that you can create a seal and also stop the pressure pushing whatever is stuck through the sink or bathtub when you start plunging.

Plunging will release most of the blockages but the more stubborn ones will require a sewer snake.

Handle The Sewer Snake With Care

If the plunger didn’t help then a drain auger or sewer snake will most likely clear the pipes. These devices have a longer reach and most of them have a blade connected at the end that will cut through the clog.

If you are going to purchase an auger note you can get a manual or a mechanical one. A mechanical drain auger will have anything from a few dozen feet of cable up to 100 feet which should cover the pipes in your home.

If however, the blockage is in the main pipeline then it would be safer to call a professional to deal with the problem.

Hydro Jet The Pipes

This is a very effective and safe way to clean the drains. A machine similar to a jet car wash is used to blast high-pressure water through the drains washing away any blockages and cleaning the pipes from the inside at the same time. Some hardware stores rent these out but if you are not confident then getting a professional will cost you between $300 – $600 to clean out your drains.

Vent Pipes Need To Breathe

If you have used the plunger and stuck the drain auger in your pipes and hydro jetted the system but still have your toilets bubbling then there is one other place we can look at before calling the plumber.

Your vent pipes that sit on your roof may be blocked by leaves, dirt, or some other material found in nature.

Simply clean the vents with a small brush allowing air to travel out, this is also a good opportunity to check if the vent pipe needs replacing.

It is a good idea to visit the roof and do a clean once every 2 or 3 months to avoid this happening in the future.

Call The Professionals

When you have exhausted all the methods we have mentioned above and the toilet is still bubbling then this is a sign of a bigger problem that needs immediate attention.

A plumber will have the know-how and expertise not to mention the tools to deal with any problem that your plumbing system has.

Once a toilet starts to gurgle and bubble things will only start to get worse so don’t delay in calling a plumber.

FAQS Frequently Asked Questions

What is the difference between a drain snake and an auger?

Drain snakes cover lines from 1-1/4inches – 2 inches and are generally for smaller drains such as the sink or basin in your bathroom or the kitchen sink. Meanwhile, drain augers cover larger lines from 1-1/2 inches to 3 inches and are meant for larger drain pipes such as your shower drain or your toilet.

Can a drain auger damage pipes?

We are told that anybody can use these devices however the truth is that if you use these incorrectly then you can actually push the blockage further in and damage the pipes. Make sure to read the instructions and follow them to the letter and if you are still not sure then contact a professional for advice or help.

How do you know if the main line is clogged?

If your mainline is clogged then you will start to get sewage odors coming from the drains such as your sink and bathtub or any other drains that you may have in your bathroom. You may also have more than one drain that is running slow indicating that a single blockage is affecting all the drains. Other signs include water backing up through the drains and the gurgling and bubbling in the drains. If you see these signs then it would be wise to contact a plumber immediately as it could lead to bigger issues if it is left unresolved.

Can a gurgling toilet fix itself?

The short and simple answer is a definitive no. You may find the gurgling or bubbling stops for a short while but it will return; however, the problem will need to be addressed before it stops for good. A blocked drain, a blocked vent pipe, or even a mainline blockage could be the cause.

How serious is a gurgling toilet?

The bubbling may just be annoying at first and may not seem very important but this could be an indication of an underlying problem that may cause you larger problems further down the line so it is advisable to investigate the problem and resolve it as soon as possible.

How much does it cost to fix a gurgling toilet?

You may find after investigating that it is quite simple to resolve this issue without having to call a plumber out, saving you those dollars.

A professional plumber can charge between $250 to $700 to clean your drainage system out. That being said, most people end up paying approx $300 for a plumber to either use an electric auger or a pressure water system to clean all the drain pipes.

No More Gurgling Bubbling Toilets 

It’s a very strange and disconcerting sound that gurgling in the toilet. We sincerely hope that we were able to provide you with the knowledge to eliminate it for good. 

Plumbers are not cheap these days so at least trying to do the easy parts can save you a lot of money plus you can be proud that you did the job yourself. We do however recommend that you hire a professional for the more complicated jobs because you don’t want to cause further damage which ends up costing you even more.