Why Does My Sink Gurgle? (Causes & How To Fix It)

While a gurgling sink can make some funny noises, those sounds are often an indicator of a much deeper issue with your plumbing.

There are a few reasons why a gurgling noise may come from your sink, and we will discuss each of them in this article.

3 Most Common Causes of Sink Gurgling Noise

1. The P-Trap is Broken

In this instance, gurgling is caused by air escaping the drain when it shouldn't. If the p-trap is blocked, it forms a vacuum that pulls on the water in the p-trap and makes air movement in the pipes audible. This is a sign that the drain is not properly venting.

2. Clogged Foods

There are plenty of things that can end up down your drain through everyday use; grease, hair, skin oils, bones, and more. If one sink is gurgling, there may be a blockage in just that drain. However, if multiple sinks are gurgling, there may be a blockage in the main sewer line. Clogs easily trap air in the pipes and make a gurgling sound.

3. Obstructed Vent Pipes

Vent pipes typically run up to the roof to expel sewer air without getting it in the house. However, a clog can make sewer gas run through the house. Blockages in vent pipes are usually caused by leaves, tennis balls, or animals and can be easily removed.

How to Fix a Gurgling Kitchen Sink: DIY Steps

1. Check sink vent installation issues

If you only hear gurgling when water is drawn from the kitchen sink, your sink vent may need to be unclogged or refitted correctly. We recommend ensuring that the drainpipe is fitted at least 3.5 feet away from the lower trap.

2. Check the air admittance valve

The air admittance valve is usually placed under the sink and is pressure-activated. Scrutinize the valve to see if it is in good condition. If you have sink issues, the valve could be trapped, immovable, or clogged. We recommend removing it, cleaning it carefully with wire and clean soapy water, and replacing it if necessary.

3. Check clogs inside the drainage pipe

Especially in low water areas, buildups of deposits and food can occur. We recommend placing a bucket under the p-trap and removing the coupling nuts with a wrench to free the p-trap. Carefully clean inside the trap with a wire brush and reassemble.

4. Check external waste in sink vents

The sink vents can easily be clogged with leaves or by other animals. Flushing water through the opening of the vent should remove the clog. However, if that is unsuccessful, we recommend utilizing a plumbing auger. Push the auger inside until it hits the blockage, then either push or pull the debris out.

5. Flush the sink

Rinse the system with water for a while and slowly increase the pressure. We recommend trying hot water first before running the cold water. We have discussed this method in other articles. Still, it is an excellent way to unstick and flush any food residue, particles, or slime from your pipes.

6. Repair the main vent

If you follow step four and still have main vent issues, you may find that the vent is damaged. In this case, it is not necessarily wise to try and fix it yourself; we recommend contacting your local plumbing professional.

Fixing a Gurgling Bathroom Sink

Bathroom sinks are used as regularly as kitchen sinks but face slightly different problems that produce similar results. Hair, skin oils, and soap can form a clogging biological slime that can cause gurgling and blockages. Some other issues that bathroom sinks can face include:

Check out this video on how to diagnose your gurgling sink:

When to Call a Pro?

Knowing these solutions is all well and good, but there are times when DIY methods are not going to cut it. If you try the steps above and still have gurgling problems, we recommend getting a professional in to help.

We also recommend bringing a plumber in if:

Why would you call a plumber? They have the tools, experience, and qualifications to help you get back on your feet efficiently and safely.

Plus, that means less effort for you. While you will need to pay for a plumbers services, it will often only cost between $70 and $300 depending on the problem to get it fixed. The length of time spent fixing the issue and cost will vary depending on the problem's nature but will be worth it regardless.

FAQs

Is a gurgling sink dangerous?

While gurgling sinks are not typically dangerous, they can release sewer gas into your home, which can be hazardous when inhaled for prolonged periods

Why does sink gurgle when the washer drains?

When a washer drains, sink gurgles can occur and are often caused by a blocked shared waste pipe.

Why does the sink gurgle when I flush the toilet?

If when you flush the toilet, the sink gurgles, you may have issues with clogged or broken pipes that may need to be replaced.

Conclusion

Knowing how to fix a gurgling kitchen sink is an easy way to save money on repairs. However, it is essential to know your limits and call a professional in for advice or help should you need it.