Loo Academy

Shower Drain Leaking Into Basement: Why & How to Fix It

Nobody likes leaks. The bane of every water system is having your water end up somewhere it’s not meant to be. When it comes to shower drains, many components can fail, which will cause water to leak into your basement.

Water leaking into your basement can begin as a few drops but can become a steady stream over time. In either case, water leaking into your basement is a serious issue that can bring about mold and structural damage.

shower drain leaking into basement
Source: Structure Tech

This article was created to help you understand the reasons why your shower drain would leak into your basement. We will also include step-by-step solutions so you can get rid of this problem.

Let’s get started!

Why Is the Shower Leaking Into My Basement?

Issues With Your Water Pipes

Your water pipes have the vital job of transporting water from one place to another. However, there are a few reasons why your pipes might not be working properly, resulting in leaks.

When your shower drain leaks into your basement, the water pipe that runs between your showerhead and shower valve is usually to blame. But any pipe that runs between your basement and shower can be the source of this leak.

The reason your pipes are leaking could be a loose connection brought on over time or through damaged threads. Rust is also another possibility when it comes to leaking pipes.

A Bad Shower Pan

Shower pans are necessary for any shower system and provide additional waterproofing to your bathroom floor.

There are concrete, acrylic, and plastic shower pans. Each one has a different lifespan, but a shower pan will last around 10 years in most cases. After which, your shower pan will fail to do its job, causing water to leak into your flooring.

A shower pan can fail before its time due to improper installation or if it’s put under additional stress through excessive weight or is struck with a very heavy falling object. Any cracks, movement, or buckling are sure signs your shower pan is experiencing issues.

An Improperly Sealed Cover Plate

The cover plate that goes over your tub’s faucet, shower drain, or shower valve and prevents the water that splashes around when showering or bathing from getting inside your walls.

When a cover plate is not sealed correctly, water will seep into your bathroom walls and down into your basement. This leak will take a long time to become noticeable but will eventually cause water damage.

Silicone sealant only lasts for so long. So your cover plate may have been sealed properly, but your sealant has simply given out. On the other hand, your cover plate may not have been installed or sealed correctly from the start.

Faulty or Worn Out Gaskets

Gaskets create a waterproof seal between two surfaces, such as a shower drain and another pipe. When gaskets deteriorate, small cracks are created, allowing water to pass through them.

Your gaskets will wear out over time, and depending on specific factors and conditions, your gaskets can last anywhere from 5 to 20 years.

Though rare, it is possible that you have faulty gaskets which were created with inherent issues when they were manufactured. These issues can severely shorten a gasket’s lifespan.

How to Fix a Leaking Shower Drain

Tools Required

  • Screwdriver
  • Channellock Pliers
  • Replacement Gaskets
  • Masonry Sealant
  • Water-based Silicone Sealant
  • Plumbers Wrench
  • Knife or Box Cutter

Solutions

Resolving Issues With Your Pipes

Step 1.
Before taking any steps to fix issues with your plumbing, you should first inspect all the pipes that are connected between your shower and your basement. 

Step 2.
Then determine whether you can resolve your plumbing issues on your own or if you should call in a professional 

Step 3.
When inspecting your pipes look for any obvious damage, rust, or loose connections.

Step 4.
If your pipes are severely rusted or otherwise damaged, your only option will be to use a plumbers wrench to replace the bad pipes with new ones. Be sure to turn off your water supply before attempting to replace any pipes.

Step 5.
Check to see if your pipes connections can be tightened, likely solving your problem.

Step 6.
If your pipe connections just spin and spin when you attempt to tighten them, that is a sign your threads are stripped or damaged, which means you need to replace those pipes.

Fixing a Bad Shower Pan

Step 1.
Begin by determining how badly your shower pan is leaking.

Step 2.
If your shower pan does have a severe leak, you are best off hiring a professional to replace it, as removing and installing a shower pan is by no means a feasible or easy DIY job.

Step 3.
If you have a minor shower pan leak, you can fix it by using masonry sealant. 

Step 4.
Simply follow the manufacturer’s instructions and apply the masonry sealer to all the cracks and seams on your shower’s floor.

Step 5.
Then wait for the masonry sealant to fully cure before you use your shower

Step 6.
It is important to note that masonry sealant will work to keep water leaking into your basement for a while, but it is not considered a permanent solution.

Resealing a Cover Plate

Step 1.
Most cover plates have screws holding them in place, so begin by using a screwdriver to remove the cover plate.

Step 2.
You may need to use a screwdriver to pry off the cover plate after the screws are removed or if your cover plate has no screws.

Step 3.
Using a knife or box cutter, take extra care to remove any old sealant stuck to your wall or cover plate.

Step 4.
Once the old sealant is removed, apply the new sealant around the inside rim over your cover plate. Make sure your sealant goes completely around the cover plate’s rim, but be careful not to overdo it.

Step 5.
Place your cover plate back onto the wall and place the screws back in and tighten them.

Step 6.
Wait for the sealant to fully cure according to the manufacturer’s instructions.

Replacing Worn Out Gaskets

Step 1.
Begin by removing your drain cover. Some drains will pop off, while others will have screws that need to be removed. Be cautious when removing these screws so that you do not drop them into the drain.

Step 2.
Next, you will remove the drain itself, which can be done with channel-lock pliers by inserting the teeth of the pliers inside the drain and turning them counterclockwise.

Step 3.
Below the drain, you will find a large rubber gasket and a friction washer. Remove the old gasket and install a new one. It’s also a good idea to use a new washer as well.

Step 4.
Use silicone sealant around the drains opening, then put the drain back in using channel locks to tighten it.

Step 5.
Reattach the drains cover. You should wait for your sealant to fully cure before using your shower.

FAQ

How much does it cost to fix a leaking shower drain?

The cost of fixing a leaking shower drain will depend on the source of the leak. Replacing a gasket or resealing a cover plate will cost you around $10 to $20. But replacing a shower pan carries a price tag in the thousands.

Does homeowners insurance cover a leaking shower drain?

Some insurance policies do cover the repairs for water damage from leaking shower drains, but others don’t. So it’s always best to check your homeowner’s insurance details to be sure.

James B. Parker

I was taught carpentry at a young age by my father. After highschool I worked with my father as a Union Carpenter for six years.

Though I no longer practice carpentry professionally I still do projects at my home and for family and friends.