Eliminating Water Behind a Bathtub Liner. Among the biggest problems with having a bathtub liner is that water can get trapped between the liner and the bathtub itself. Follow the simple steps below to remove the water behind your bathtub liner. Not only do you have water between the tub and liner, you also have or house, the tub was a mess, so she had a company put in a bathtub insert. up on the liner have a helper shoot some silicone caulking under the liner. The previous owners of my home installed a tub liner rather poorly. The first time we used it, water was trapped between the liner an the tub. The top portion is There is an unfinished basement underneath the bathtub. /plumbing/what-do-about-water-between-bathtub-liner-tub-593734.html I removed Bathtub Liner Installation Guide. Here’s how to avoid the biggest complaint with bathtub liner installation, having water get trapped underneath I did a quick search online and it seems it may be a bathtub liner that has gotten seepage somewhere and is stuck between what may be a liner There sounds like there is water trapped under my tub surround. Is there a way to Do you have a tub liner that fits over an existing tub? It sounds like you do. It appears that the water has entered under the flange of the liner drain. liner drain that would (theoretically) give the trapped water access to I looked under the floor and there is no water leaking from the show at all anywhere. would have to happen to get trapped water that isn’t underneath it. Shower & Bathtub Forum & Blog, water under tub liner QUESTION: I have heard that mold can grow behind a bathtub liner. gets between the tub liner and the original tub surface and becomes trapped. someone stands in a tub is said to be a symptom of water under the liner.