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Sink Drain Leaking Around Threads: 3 Reasons & Solutions!

You woke up in the morning and saw the bathroom sink drain leaking around the threads. In that time of hurry, it’s a very annoying situation. 

Are you looking for why the sink drain is leaking around threads?

Bathroom sink drain leaks are caused mostly by a broken thread. But in certain cases, by a malfunctioning drain. Leaking might also occur if the sink screw is not properly tightened. If the problem is a damaged thread, it won’t take long to remedy. So, you have to take action immediately. 

Continue reading to learn what causes leaks around threads in bathroom sinks and how to remedy them. You can also discover some tips and tactics to help you complete this task quickly.

3 Reasons for Bathroom Sink Drain Leaking Around Threads

You need to determine the problems before repairing the bathroom sink drain leaking around the threads. 

Understanding what creates the problem makes it much easier to develop a long-term remedy. There are three basic causes of leaky bathroom sink drains. 

  1. weak caulking between the thread and the pipeline
  2. drain unsealed
  3. sewage damage

To properly resolve the issue, you must first determine the source of the leak. And also how you can tile around the floor drain. The procedures below can assist you in determining the root cause of your bathroom sink drain leaking:

Reason 1: Loosened Screw

The first step in determining if the bathroom sink drain is leaking is to thoroughly inspect the nuts. Use a screwdriver to determine whether or not the screw is secure. You could also check to see whether the nut is rotating around the gasket.

Reason 2: Ruined Threads

If you’ve examined the screw and it’s still undamaged, you’ll go on to the thread. Teflon tape is typically used to attach the drain. However, it might become ruined with time. Remove the old Teflon tape and exchange it with a fresh one to eliminate leakage all around the thread.

Reason 3: Broken Drainage Seal

If you examine the screw and threads, they are still in fine shape. The drain is the next item you’ll have to skimp on. Two critical components must be thoroughly examined: the drainage seal and the silicone gasket. 

If the drainage seal or the silicone gasket on your bathroom sink is compromised, it will leak. Leaks could also be caused by a fracture surrounding the sink.

3 Steps To Repair Bathroom Sink Drain Leakage Around Threads

The manner of repair will differ depending on the type of leak. Here are the steps to take depending on the sort of leak.

Step 1: Tightened the Screw 

Did you discover that the screw in the drain is not securely fastened? Then, using an adjustable wrench, gently tighten the nut. However, don’t apply too much force, since this might harm the screw. 

Slowly tighten the screw and inspect to see whether water is leaking from that specific spot. Switch on the faucet and examine the threads attentively to see if there is any water damage. If the screw is broken, it must be replaced.

Step 2: Apply New Thread Tap

The sink drain will leak if the thread is not fastened. A broken thread might cause a bathroom sink spill to leak. To repair it, use a wrench to loosen the screw from the drain. Disconnect the drainage pipe and inspect it for any plumber’s tape.

Remove the existing one and wrap the new one around the drainage pipe and the sink faucet. Connect the drain pipe and tighten the nut, and everything should be alright.

Step 3: Drain Fixing

Because of wear and tear, the drain pipe may leak after a long period of use. A clogged drain can also lead to bathroom sink overflow leaks. To locate the leak, inspect each portion of the drain, including the gasket.

Replace the silicone gasket and secure it to the drain. Instructions for sealing a sink drain may be found later in this article.

Tools Required to Repair a Leaked Sink Drain

When trying to repair your leaking sink drain, you need some tools to do that. These five tools are a must-have in your house. 

  • Wrench with Adjustment
  • Plumbers’ Tape
  • Putty for Plumbers
  • Caulk Silicone
  • Clicker Drain Seal

These are all the repair tools you need for sink drain leakage. You can find all the products below. 


These products are long-lasting at a reasonable price. 

How Should a Bathroom Sink Drain Be Sealed

You must first remove the prior sealant to seal a bathroom sink drain. Remove the old sealant from the drainage flange’s bottom. You might have to remove the caulk with a putty knife. Everything that was blocking and closing the drain was removed.

To secure the drain hole, add silicone caulk around it. You may also need to caulk around the sealed grout. At this time, you can also apply a plumber’s putty. Then carefully lower the drain flange and fasten it to the sink.

How Do I Tighten the Screw Under the Sink

Is the screw underneath the sink too loose to keep the drainage in place? Not an issue! Grasp the bottom of the screw with pliers to prevent it from moving or spinning. 

Tighten the screw gently using a wrench. Secure the screw by turning it clockwise. To avoid harm, don’t apply too much force.

8 Tips for Fixing Sink Drain Leakage Around Threads

Here are some tips to ensure that your repair produces the desired results:

Tip 1: Avoid Unnecessary Tightness

You might overtighten the slip screw in an effort to stop leakage. This may result in screw and sink damage. Tighten the screw until it feels snug, plus another quarter of a complete revolution.

Tip 2: Ensure Before Running Water on Silicone 

If you use silicone caulk to cover the drain, allow it to dry for the appropriate amount of time. Before using any plumbing item, thoroughly read the instructions.

Tip 3: Inspect the Sink Neck When Replacing the Rubber Gasket

Even though you replace the rubber gasket with a new one, you might still have issues. Look for minor fractures in the sink collar to prevent additional leakage. They might prevent the gasket from sticking entirely to the sink collar.

Tip 4: Check the Rubber Gasket 

Avoid low-cost alternatives, such as gaskets made of plastic rather than silicone. Rubber is used for gaskets since it is more malleable than plastic. Although silicone may work well, avoid plastic since it does not mold around the thread.

Tip 5: Disassemble the Drain

Pull the drain apart and rebuild it, even if it appears difficult. Repairing the leak may help for a while, but further leaks are expected in the future. Water damage will require a significant amount of additional labor.

As a result, you should always inspect the drain pieces for damage. Replace any broken or damaged parts first, and then apply direct silicone or other seals.

Tip 6: Don’t Forget about Sealing

It may happen that using Teflon tape for sealing is not mentioned in the sink installation guide. Every experienced plumber understands the importance of thread sealing. Even if the drain is correctly built, you would still need to seal it.

Tip 7: Turn the Tape Clockwise

Applying Teflon tape backwards rather than clockwise is a typical DIY beginner plumbing error. This is incorrect since the tape will unwind from the threads as you adjust the fitting. This eliminates the tape’s complete sealing effect.

Tip 8: Proceed with Caution After Repair Appears to be Finished

Sink drain leakage can be extremely tiny and sporadic. Even if you stream water after a fix to assess the outcomes, they may go undetected. 

Put the newspaper in the bottom cupboard underneath the sink. This not only covers your cupboard to some level but also aids in locating leaks.


Should I use silicone or a plumber’s putty to repair my sink drain?

Sink drains could be sealed with silicone caulk or plumber’s putty. As the concrete dries out, the cleaner’s putty may split and leak. However, it is the preferable sealer if you will be altering or removing the drain.

Can PVC cement be used to seal a leak?

Connecting a pipe to a pipe fitting necessitates the use of a carefully designed primer and cement. Not just any old glue, but a chemical solution that dissolves the top of the PVC. It re-hardens swiftly to fuse the parts together. The end result is an airtight, leak-proof connection akin to metal soldering.

Is it okay to use a plumber’s putty on a plastic sink drain?

The quick explanation is that putty may damage plastic and create leaks. Most putties are made from petroleum. This oil makes the putty malleable and moisture-proof. But it can damage plastic plumbing components and break them down over time.

Wrapping Up 

As we are at the end of the article. Hopefully, it will clear all your doubts about the sink drain leaking around threads. Simply follow the processes and recommendations we discussed. There are a few tools available to assist you in doing it yourself. 

If you have previously followed our advised procedure and it does not appear to be working, you should contact a plumber.

That’s all I have for you today. Be safe and sound. Ta-ta!