Loo Academy

Leaking Shower Pan: Common Causes & How To Fix Them

A leaking shower pan is a serious problem that can cause severe damage to your home.

And the longer you wait to fix it, the more damage it does and the more expensive it becomes to repair.

leaking shower pan

To prevent future expensive repairs, learn how to identify whether your shower pan is leaking and how to fix the most common causes of leaks.

Common Causes

Shower pans are a liner typically made of PVC. They are placed under the mortar beneath the floor of your shower. The shower pan is the last line of defense between your shower and your home’s foundation.

There are many reasons a shower pan can leak, but they usually revolve around lousy installation or a very old shower pan. 

If the shower pan is not installed correctly or is punctured, typically with a screw, leaks will happen. These leaks will rust the bolt or screw, allowing the water to seep into the wood of your foundation, causing structural damage.

Installation blunders besides penetrating the pan include not considering where the drain pan will be or where the glass or walls will connect to the shower.

All these installation mishaps will give you the same result, leaks that cause structural damage.

How To Tell If Your Shower Pan Is Leaking (Shower Pan Test)

Cracks, leaks, and movement are signs that your shower is in bad shape.

There are a few ways to test for a shower pan leak. But there is one specific test that I find to be the easiest and most accurate.

You will need two items for this test, one being a rugged silicone-based waterproof tape. You can get this type of tape from manufacturers such as 3M, Flex Tape, and Gorilla Tape. The second item you will need is a ruler or tape measure.

  • Step 1. Begin the test by thoroughly covering the drain of your shower with waterproof tape.
  • Step 2. Once your drain is sealed by the tape, fill your shower with 1 to 2 inches of water.
  • Step 3. Use your tape measure or ruler to note the level of the water. 
  • Step 4. Return 12 to 48 hours later to check the water level with your measuring device.

If you have a bad leak, you may see a drop in the water level as soon as 12 hours. Otherwise, it may take up to 48 hours.

If 48 hours have passed and there has been no drop in the water level, your pan is in good shape. But as long as you taped your drain well, any reduction in the water level indicates a leak in your shower pan.

How To Fix Shower Pan Leaks

Once you have determined you have a leaking shower pan, how do you fix it?

There are three generally recognized methods that can fix your shower pan. The method that works best for you will be based on your particular situation and how bad the leak is.

Masonry Sealer

Using masonry sealer shouldn’t be considered a permanent fix. It can fix your shower pan if you have a minor leak. But in general, a masonry sealer is used as a temporary fix so you can stop the water damage and continue using your shower until you can remove and replace the shower pan.

You would apply masonry sealer to all cracks and seams on your shower floor. Applying masonry sealer is an easy DIY project and should not cost you more than 25 dollars.

Repair The Grout

The grout that runs across the floor of your shower will eventually give out and can be a major reason for a leaking shower pan.

If the grout in your shower requires you to mess with the floors or foundation to repair the grout, you’re better off calling a professional.

If you can re-grout without pulling the floors, it is just a simple matter of mixing and applying the grout then sealing it. Using an unsanded epoxy grout will not scratch your delicate tile or marble, and it will even seal itself.

Repairing grout is a medium-sized DIY project as it will take more time and labor than masonry sealant and will cost you around 20 to 40 dollars.

Replace The Shower Pan Liner

If you have a significant leak beyond what grout repair can handle, you may have no other choice than to replace the shower pan liner.

Shower pan liners only last so long, and when their time has come, you must replace them. But only replace your shower pan liner if you have no other option unless you are a skilled craftsman; I would not recommend this as a DIY project.

Depending on the home and the bathroom, replacing the pan’s liner will involve opening up walls or flooring. The average cost a professional will quote you for this type of work will be anywhere from 1000 to 3000 dollars.

If you decide to take this project on your own, some guides and resources can help you. Your cost will go down if you do the labor yourself, as the materials will cost you around 600 dollars.

FAQ

How long should a shower pan last?

A shower pan will generally last for 20 years. The life of the shower pan will be affected by things like how often it is used and how quickly you respond to and fix any damage. Without heavy use and with extreme care, your shower pan may last up to 25 or 30 years.

Does insurance cover shower pan leaks?

In most cases, they do not. If you have water damage protection in your coverage, generally, insurance will pay for the damage caused by the water leak, but they will not pay to replace or repair the appliance that caused it. All policies are different, so make sure to read the fine print of yours.

How much does It cost to repair a leaking shower pan?

This will depend entirely on how bad your leak is. If your leak is minor or moderate, repairing the grout may solve your issue for around 40 dollars. If your leak is horrible, you may have to replace the shower pan, costing you upwards of thousands of dollars.

Conclusion

Shower pans can be tricky, as they are sandwiched between your flooring and your foundation, so you cannot see them. You will have no idea of the state of your shower pan, what materials it’s made of, or even how long it’s been there unless you get information from a contractor. It is something to consider when buying a new home or moving into an older house. If the shower pan has been down there for over 30 years, be cautious and prepared for possible problems.

Fixing a shower pan leak can be an easy, inexpensive repair on one end or a problematic, costly repair on the other side.

If you have a shower pan leak, I would advise you not to ignore it. At the very least, apply some masonry sealant to buy you time.

Going through the process of repairing grout will save you a lot of money compared to removing the shower pan itself.

In most cases, you cannot depend on an insurance company to pay for the cost of replacing a shower pan.

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.