Fix Your Leaking Bathroom Sink In Just 4 Easy And Quick Steps! 

It can be incredibly frustrating to have a leaking bathroom sink with no idea how to fix it.

Not only that, but a leaking bathroom sink can actually prove to be quite dangerous.

Fix Your Leaking Bathroom Sink In Just 4 Easy And Quick Steps!

It can cause significant damage to your floors and subfloors if you do not deal with it right away. 

However, there is no need to panic! There is a very easy and quick solution to fixing your bathroom sink that has a link underneath.

In this article, we will take you through the four steps that will allow you to fix your bathroom sink in no time, and more! 

So, if this is of interest to you, then read on! 

How To Fix Your Bathroom Sink With A Leak Underneath: What You Will Need

It is important to note before we get into the method that these steps will not cover every single leak that can happen in your bathroom sink. However, four of the most common issues will be covered! 

For each of these issues, you will need to have: 

  • Split-joint pliers or an adjustable wrench 
  • An old rag 
  • A bucket 
  • Teflon tape 
  • Plumber’s putty 
  • Long-nose pliers 
  • Any parts of the sink that need to be replaced 

Now that we have that covered, let’s get into the steps and have your bathroom sink fixed in no time! 

How To Fix Your Bathroom Sink With A Leak Underneath: The Method 

The following steps will help you fix your leaking bathroom sink, provided the link is underneath the sink. Let’s get into it! 

Fixing Your Bathroom Sink Step 1: A Leak At The Drain Body

This first step applies to bathroom sinks that have a leak at the drain body only.

This is where the water will leak from the area where the pivot rod and the drain body meet. If this happens to you, then here is what you can do! 

  • First, you need to take your slip-joint pliers or adjustable wrench and tighten the retaining nut. 
  • Then, once you have completed the step above, you need to inspect the sink. If you find that it is still leaking, then you should remove the retaining nut and the pivot rod from the drain body. 
  • Once removed, you will need to replace the gasket or washer, which you can find under the area where the retaining nut was situated. 
  • If you still notice leaks once everything has been put back, then you need to check the lift mechanism. If you notice it is damaged or worn, then it is best to replace it. Alternatively, you can try to replace the pop-up assembly or drain the body to see if this fixes the issue.

Fixing Your Bathroom Sink Step 2: A Leaking At The Trap 

This step will show you how to fix a leak in the bathroom sink if the leak is in the trap.  

  • First, you will need to make sure all of the locknuts and slip nuts are tightened at a quarter-turn. Here, you should not be aggressive, but it is important to be firm.
  • Then, you need to take a dry rag and clean the trap assembly as a whole. 
  • Here comes the test. Run the faucet so the basin fills with water. 
  • If you notice leaks forming at the slip nuts, it is time to remove parts of the trap, such as the bend and arm, and once you do so, change the washers. 
  • If you notice that the arm or bend of the trap has been corroded or otherwise damaged, then you will need to replace this, too. 

It is important to note that before you replace the trap, you need to ensure that there is no leak at the sink flange or tailpiece of the sink.

If there is, go to step three to see how this can be fixed before resuming this step. 

  • Now, you need to replace the trap. If you notice that the trap arm is too big for the drainpipe, then you can trim it down until it fits. As a general rule, the trap arm should reach 1.5 inches inside the adapter. 

Fixing Your Bathroom Sink Step 3: A Leaking At The Tailpiece 

Next, we will detail what you should do if there is a leak at the tailpiece of the bathroom sink. 

  • First, you need to take a wrench and unscrew the tailpiece. However, it is important to note that if your tailpiece is made from brass, then it can easily be crushed by you doing this, so you must be careful. It is best to use your hands to unscrew brass tailpieces. 
  • To get a better grip on the tailpiece while you complete the above step, you can put a rubber band over it, which will stop your hand from slipping as you attempt to get the tailpiece to loosen. 
  • If your tailpiece really won’t budge, then it is best to use the wrench to remove it and then buy a replacement, but hopefully, you will have already removed your tailpiece and can skip this step. 
  • Next, you need to check if any of the tailpiece parts have been left over after you have removed it. This can happen to older tailpieces, so just take your long-nose pliers and take out any thread pieces left over in the drain body. 
  • Now, you need to take some Teflon tape and wrap it around the threads. 
  • Once you do this, you can replace the washer and trap’s slip nut. 
  • Finally, you can go ahead and replace the tailpiece. 

Fixing Your Bathroom Sink Step 4: Leaking At The Sink Flange 

Cracked putty or a worn washer under your sink flange is what permits water to leak below the sink.

Here are the steps you can take to fix this issue! 

  • First, you need to remove the trap bend. 
  • Now, you need to take away the drain body. 
  • Once you have completed the step above, you can go ahead and apply a strip of plumber’s putty to the flange lip. It is best to follow the manufacturer’s instructions when you do this. 
  • Then, you can go ahead and put the pop-up assembly and the drain body back. 
  • Now, all you need to do is wipe away the excess putty that may be sitting around the flange with an old rag. 
  • If you notice that the leaking has not stopped, then you need to, using quarter-turns only, tighten all of the connections on the sink to ensure that the leaking stops. 

Final Thoughts

So, there you have it! A bathroom sink with a leak underneath is not just an inconvenience for you, but it can actually prove dangerous because it may leak onto the floors and subfloors, having the potential to cause unnecessary accidents and corrosion overtime. 

However, there is no need to panic! It is very easy to fix your leaking bathroom sink.

There are four common leaks you can have with bathroom sinks (Check out Removing A Bathroom Sink Stopper).

They are a leak in the drain body, in the trap, at the tailpiece, and at the sink flange.

You will need roughly the same equipment for every one of these problems, and it is important to make sure you have these sorted before you begin to work on fixing the sink.

We have detailed four different solutions, one for each problem.

So, all you need to do is work out what part of your sink is leaking and then follow the steps to fix it, it really is that easy! 

However, if you find any of these steps too difficult, or the leak is coming from elsewhere in the sink, then it is best to contact a plumber so they can fix the issue for you. 

We hope this article taught you all you need to know about fixing a leaking bathroom sink!

Adrienne Carrie Hubbard
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