Home Improvement

Leaking Sink: Causes and Solutions

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Repairing things at home is always daunting, especially when it’s your first time dealing with a problem. How hard can it be to fix a leaking sink? There are many reasons for what might have caused the issue, from the most minor to the most urgent. We will go through common problems and their solutions and how you can handle this situation. Sometimes the problem might require calling a licensed plumber, as the state laws in Australia require. Let’s go!

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Table of Contents

Locating the problem

First things first, let’s start by locating the problem. Equip yourself with a bucket or a large container, towel, flashlight and patience.

  • Empty your sink; you don’t want any dishware to be in the way.
  • Turn off the faucet (if possible).
  • If the faucet is dripping, place a large bowl under it to collect the water. You need to isolate this problem to see if anything else contributes to the leakage.
  • Using the flashlight, inspect under the sink – is there any leakage when the sink is not being used? If the answer is yes, it’s most likely a problem with the water supply line.
  • Turn on the faucet (and remove the bowl first, of course). Is there leakage now? Where does it come from? You should look for broken pipes, loosened-up joints, and damaged sealant. Doing this will give you an idea of what needs to be fixed.
  • If you’re lost in the terminology, here’s a little bit of plumbing vocabulary.
Before you even attempt fixing your sink, always turn off your main water valve. If you don’t do that, you’re going to have a flooded place and bring yourself additional problems.

Fixing your leaking sink

After locating the issue, turning off the main water valve and equipping yourself with the tools you need, it’s time to get to business so you can finally fix that leaking sink. Below you can find the most common problems and their solutions.

Problems with the water supply line

After you’ve done your inspection and noticed that the leaking is constant and not only when you use the sink, then the problem is most likely in the water supply line. It’s under pressure all the time, which causes constant water dripping. So that’s why it’s hard to miss if there’s a problem with the valves or the supply line itself.

Solution: Try tightening the retention nut on the supply valve. If the leaking continues, the valves of the supply line need to be replaced. They can get loose from contraction/expansion, and they can deteriorate from age.

However, problems can also come from the water supply pipes. If they’re damaged and leaking, you can apply pipe sealant to stop the leak. If this doesn’t help, the whole system might need changing. If you’re not confident you can do that on your own, you should definitely call a professional plumber.

When cleaning up after a water leak, use fans to dry out your place. If possible, leave them running non-stop.

Burst pipes

This plumbing emergency demands immediate attention, so let’s get straight to the point.

Solution: Start by calling a plumber in your area! Then, shut off the valve under the sink or the main water supply to your home. Be careful with any electrical connections that might have gotten wet during the accident. Turn off nearby appliances! We don’t want any electrocutions over here.

A temporary solution to stop the leaking is to duct tape it. Clean and dry the area before application. You can conceal pinpoint punctures, but remember that this might not hold up for too long, as the water pressure might loosen it until it starts leaking again.

A solution that will last longer is to secure the pipe with a sleeve clamp or a hose clamp. It can fix smaller to more significant leaks. It comes with a gasket material that you wrap around the pipe before securing the sleeve clamp. A piece of rubber is used for the hose clamp. It’s placed on the pipe with the hose clamp tightened around it. That should do!

The best solution is to replace the burst pipe. That’s the permanent solution to your problem.

Burst pipes are nothing to postpone. Contact a licensed plumber to fix the issue!

Leaking sink drain traps

This leakage type is only visible when the sink is being used. The pipes can be plastic or metal, and how you fix them is different.

Solution: If the drain pipes are plastic, try tightening the nuts with your hands. In case the leaking doesn’t stop, you can take the joints apart and add sealant to them or silicone grease. If that doesn’t help also, you might need to replace the pipes.

Check the material from which your pipes are made. Those that are metal, like brass, copper, galvanise, etc., might be rotting, so you will have to replace them. If not, just hand tighten the nuts and then with pliers.

Leaking P-trap (water trap)

Do you see that U-shaped pipe under your sink? That’s the P-trap. The p-trap has multiple services, one of which is stopping the sewer gasses from coming back into your home. Over time it can get clogged, which causes it to overflow, and you can see the result of that as a leakage.

Solution: The solution to fixing a clogged P-trap is easy. Get a bucket and roll up your sleeves, as it’s going to get a bit messy. Put the bucket under the P-trap. Disconnect the trap and empty it in the bucket and then reinstall it back on. When you reassemble it, tighten the nuts but don’t over-tighten them.

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Basket strainer leaking (sink drain)

One of the most common leaks in a household is a leaky basket strainer. It can be caused by broken parts that need replacement. The good news is that you can get a new basket strainer assembly at a reasonably low price.

Solution: Unscrew the strainer, clean the sink’s surface until it shines, and then dry it out. Inspect the assembly if it has broken parts. If it doesn’t, you can still reuse it but clean it and dry it first. In case it’s broken, use a new strainer. Repack with plumber’s putty. Clean up the excess putty with scrapers and dry cloth.

When applying sealant or putty, you need to be working on an incredibly clean and dry surface and hands. Otherwise, they won’t bond.

Leaky faucet

Drip, drip, drip, drip. It can make a person go insane. Not to mention the cost of the water bill at the end of the month.

Solution: First, you need to find out which side of the faucet is dripping. The quickest way to do that is to place your hand under the dripping tap and feel the water. If you’re still unsure or think both sides might have issues, underneath the sink, you should have two valves – one for the hot and one for the cold water. Turn off one at a time to determine which side causes the problem. After that, turn on the faucet to empty it of any residual water.

Remove the handle and retainer nut. Pull out the cylinder. You can replace the whole cylinder with a new one or only its seals. If the valve stem is ceramic, unscrew it and pull it out. Then remove the gasket and clean everything under running water. Add a bit of a plumber’s grease and reassemble everything back together. You can use a new gasket if needed.

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Mixer tap leaking

When the mixer tap leaks, it usually drips underneath the sink, making the illusion that the problem is somewhere down there.

Solution: First, turn the water off. Remove the handle and dome of the mixer tap. Inspect the locking nut – is it too loose? If yes, tighten it with a wrench and see if that fixes your problem. If not, continue disassembling the mixer tap. Near the base of it, there is a seal that might have ripped apart and needs replacing. If it’s intact, clean the built-up on and around it and assemble the mixer tap again. Gunk can be getting in the way and causing the leak.

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  • Don’t postpone any plumbing problems. They won’t go away on their own and can only worsen with time. On top of that, you can have severe water damage, which is a pain on its own, especially if you’re renting. So the sooner you fix any leaks, the better.
  • Before starting, turn off the water supply valve. You don’t want to flood your home.
  • Inspect, repair/replace, test. Always test at the end if you’ve successfully fixed your leaking sink. You can place some paper underneath and use it to indicate if the problem is still present.
  • And remember that you don’t have to repair a leaking sink on your own and can always call a professional plumber to the rescue.

The troubles with the sink don’t seem to end? Contact a licensed plumber to fix the issue!

Disclaimer: We are a commercial home maintenance service provider. Our purpose with this blog is to provide valuable and accurate content for solely informational purposes. We strongly advise our readers to consider all the risks and health concerns before taking a DIY project. We also highly recommend you get fully informed about the laws and regulations regarding electrical, plumbing and other work in the different states of Australia.

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Haris Parikh
Haris Parikh
3 years ago

Interesting post. Thank you for sharing solution of common water leakage problem.

Plumber Fremont
Plumber Fremont
3 years ago

Thanks for sharing beautiful post.

2 years ago

My mixer tap was leaking, and as you mentioned the problem was under the sink. Thank you for a great article

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