For a long time, the only materials used in building shower pans were cast iron or pre-formed fiberglass. Both work great and are still used today, but there is also an option that has become popular: polymer (or plastic) shower pans. Polymer pans offer several benefits over the other options: they are lighter weight, easier to install, and less expensive.

The problem with polymer pans, however, is that they can be prone to movement or sinking. Fortunately, this problem is easy to fix.

If you have a shower pan that flexes or moves when weight is applied, it may be an indication that the pan and base were installed improperly. The following steps will help solve this problem: 

Step 1 – Make Sure Base is Installed Properly:

If you have tried the previous steps and your shower pan still moves, it may be due to incorrect installation of the base. To check for this, remove the base and check the installation. 

If the pan has been installed directly on top of a concrete floor, without a layer of self-leveling cement between them, then the most likely cause of the movement is that there is nothing holding it in place. A membrane that will bond to both materials should have been placed down before installation. If this is not present, a layer of self-leveling cement should be placed down before the shower pan is installed. 

If you have tried these steps and your base is still moving or flexing, read on to Step 2.

Step 2 – Check for Rips and Loose Surfaces: 

To support movement, a membrane that will bond to both materials must be placed down before installation. If this membrane is damaged or missing, the shower pan will sink when weight is added, damaging the surrounding surfaces. Repair these membranes with an epoxy bonding agent and allow time for them to cure completely. 

Step 3 – Repair the Subfloor:

If you have a tile floor and the grout around tiles is loose, it could be an indication that there is a problem with your subfloor. This can be repaired by applying a new layer of thinnest over the old one.

If you do not have tile and the surface appears to be in good shape, then you can proceed to Step 4. 

Step 4 – Apply Caulk: 

Once the surface has been prepared, it is time to apply caulking. Silicone caulking is a good choice for this because it can expand and contract with movement. Apply a continuous bead of caulking around the outside of the shower pan. 

Step 5 – Level the Pan: 

Once the caulking has dried, it is time to level the pan. You can do this by using shims to adjust the height of the pan until it is even with the surrounding surfaces. Once it is in position, use a level to check that it is straight. Finally, tighten the screws or bolts that hold the pan in place.

If you have followed these steps and your shower pan is still flexing or moving, it may be necessary to replace the entire unit. Consult with a professional to determine the best course of action. Get more tips like this from chriply.com