Sink Gurgles When Toilet Flushes: Noise Removal Guide

Anyone who’s ever had a problem with gurgling drains will tell you to try and fix them right away and there is a very good reason behind that.

It’s very important that you know that gurgling drains can be a strong indicator of a larger plumbing problem, which is why you should investigate your plumbing system and solve this as soon as possible.

Whether you’re having trouble with the gurgling noise from your bathtub drain, toilet, or sink, don’t let it continue for too long, because there are practical solutions for all of these problems.

gurgling sink when toilet flushed

My Experience

I personally had this exact problem a couple of weeks ago when my sink started to make gurgling sounds anytime I flushed the toilet.

Once I started researching how I should approach this problem, I was relieved to find out that it’s much easier to get rid of the noise when it comes from the sink than the noise from the bathtub.

When I found out that the gases from the sewer could come into the bathroom through my vents if I let this continue, I must admit that I was a bit scared and I immediately started to work on this.

Not only do the gases from the sewer smell horrible, but they also contain lots of methane and hydrogen sulfide, both of which are extremely harmful and toxic when inhaled.

Why does your sink make gurgling noises when you flush the toilet?

Before I let you know how to get rid of this problem, I have to explain to you how this happens and why.

There are a few different causes of this problem and most of them have to do with clogged, blocked pipes that aren’t properly vented.

When the pipes are clogged, the water can’t go through them the way it normally should and this is when blockage happens.

Of course, the problem can be even bigger than this, which means you won't be able to solve it by simply clearing out your pipes.

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You might need to hire a plumber to repair some pipes or you can even repair them yourself, but do keep in mind that repairing pipes is not a joke and you should not try to do it if you're completely inexperienced in that kind of work.

You might even need to get someone to install new pipes for you if the problem is really not fixable, but this will not be necessary in most cases.

What to do if your sink gurgles when toilet flushes

There are many ways to get rid of the gurgling noise coming from your sink, and I will make sure to present you with the best of them so that you won't ever have to deal with this problem again.

Before you begin this little project, you will need to buy or borrow a couple of things that will be necessary if you want this to work:

  • Plunger
  • Ladder
  • Garden hose
  • Sewer auger
  • Pliers
  • Valve for air-admittance

Once you’ve made sure that you have all the material you need, you can finally start working.

1. Plunging

The first thing you need to do tightly seal the sink drain. Once you’ve done that, you have to plunge your toilet.

You’ve probably done this before at least once in your life, so it shouldn’t be too big of a problem to go through with it.

Now, if your pipe is blocked by something, when you start plunging your toilet, this blockage will probably make the air go out through the sink drain and the blockage will be removed.

By covering the sink drain while you do this you’ll make sure that the plunger is effective.

sink-plunger

Once you've finished doing all of this, you can finally open the drain. Try flushing your toilet to test if this worked.

Now, if you can still hear the gurgling, you should keep on plunging and try again. If you're sure that this doesn't work, you have to try another option.

2. Cleaning the roof vent stack

Now, this is a bit more complicated and can be quite tricky if you have a fear of heights. You will need to go up to your roof and find your main vent stack.

It is quite common for the stack to get covered by leaves or some other kind of debris and its screen will probably be dirty from the exposure.

You should clear both the debris and the screen. If you can get a garden hose up to the roof, that will be of great help to you, because you can use it to clear out the vent pipe.

If this doesn’t work and the water keeps flowing out, that means that there is a huge blockage that you can’t get rid of by only using water.

You will need to use a sewer auger, which you probably don’t have, but you can easily rent it for a fair price or have someone lend it to you.

Using a sewer auger can be a bit too complicated for some people. If you don’t think that you can pull it off, there is always the option of getting a plumber to do the work or getting someone more experienced to help you and guide you through it.

If you do decide to do it on your own, you will certainly save yourself some money and you will be able to help someone else who might have the same problem as you.

First of all, you will need to put the auger into the vent opening. You have to unwind the auger until you start to feel some resistance from the blockage.

Once you feel it, you have to crank the handle and keep pulling the head of the auger out from time to time in order to get the debris out.

When you can no longer feel any resistance, you can finally spray some more water from the garden hose into the vent to clear it out a bit more.

3. Replacing a valve

If none of this works, there is still one more solution left. You can take a look under your sink. You will see a cheater valve there.

What you need to do is to unscrew the valve and put a new one in its place. The valve is quite cheap and you will save a lot of money by replacing it yourself instead of getting a plumber to do it.

Final Word: On Gurgling Sink when Toilet Flushed

In conclusion, regardless of how tolerant or intolerant you are to noise, if you hear gurgling sounds from your sink when you flush your toilet, don’t wait for the noise to go away on its own.

The gurgling noise is almost always a sign that there is a huge problem with your pipes and you should never ignore it.

There are many easy ways to fix this problem and now you know all of them. You won’t need to put up with the noise anymore and you can rest assured that you’ll be safe from the sewer gases and methane.

I wish you the best of luck and hope that you’ll find my advice helpful.