I've moved into this house a year ago and have put up with the master bath shower that was installed incorrectly. The one piece stall was put in with very little support in the space between to fiberglass floor and the sub floor underneath. It sqweeks and flexes quite a bit but has not broken (YET!)
Is there any way to build up the space without trashing the stall? Is it worth saving or should I just rip it out and put in a one piece pan and tile the walls? I had thought of injecting some type of resin or expanding foam but would that create more problems down the line?
I'm 99% sure the subfloor has no damage since it is strong, clean and dry underneath. The bath is over the garage in a split level. I had thought of doing any foam injection from the bottom and patching the hole from underneath. Is this a bad idea?