First let me start by saying that if YOU have tile in your tub/shower area YOU are susceptible to this problem, unless it was installed correctly (unfortunately 80-90% of the ones i tear out are not).
We recently worked on a bathroom that was only a few years old, and due to improper installation had cracks form in the grout lines. It appears that a previous owner had either had the builder or another contractor try to address the issue but failed to address it properly. The current owners had decided to have it fixed correctly and that’s where we come in. The crack that the homeowner could see were not as extensive as what is in the photo (i wanted to see how far the damage was that was hidden so i pushed on the wall a little, and the cracks opened right up). These cracks were not the homeowners fault, it wasnt a “maintenacne” issue. None of the drywall that the tile was mounted to was seamed. Let me say that again: 1. they used MR drywall not Hardi-board, or Wonder/Concrete board. 2. They didn’t “seam” the drywall (that means the wall will move in sections as opposed to moving as one, it also doesn’t allow for expansion or contraction). Heck one of the walls i removed only had about 6 nails in it, 6 NAILS. Routine maintenance wont fix those, constant “re-grouting” wont fix it; it was a cheap builder allowing cheap subs to work for him, another reason why home-builders make poor remodelers but i digress.
Anyhow, the scope of the job was originally to remove the existing shower and install a new shower (KBRS base, with tile walls, “schulter” water proofing is to be used on the walls and floor; new shower door and tile floor). Once we started demolition it became apparent there were bigger issues. The water leak had soaked through the drywall (causing rot, mold and mildew) and had even soaked through the insulation. There was so much moisture that the exterior foam board was collecting moisture pellets on it between it and the insulation. The metal bracing straps that the builder used for structural support had even started to rust. There was even water pooled on top of the bottom wall plate. Needless to say the scope of the job changed. The original goal today was to tear out build back and water proof everything. Due to the excessive water damage the goal for the day was to tear-out, prep the floor, and set up fans to dry out the wall cavity. Hopefully the studs will dry and we wont have to replace them, but if we due then we will. Tomorrow will be (assuming its dry), wipe down the mold/mildew with a cleaner, re-insulate, put up the walls and waterproof it, then tile the floor. If its still wet then we’ll only be able to tile the floor, and the rest will happen later in the week. Either way the lesson here is cracks in the grout can allow for major water damage, AND when we are done this till never be an issue for them again. We warrant against leaks for life.