There is extensive cracking in the grout along the upper portion of our shower side-wall, both inside and outside of our shower. We've also noticed a leak in the shower wall, likely due to the fact that water pooling on the upper inside portion of the side wall enters cracks in the grout, exiting on the outside of the half wall along another crack (see images, with region where water exits the wall circled and arrows pointing to flow of water droplets onto the floor). Given that we don't know the materials used in constructing this side wall we are foreseeing water damage and potentially mold issues, and sadly assume we'll have to tear down and rebuild.
The bathroom is located in a portion of the house that has significantly settled. We are awaiting a permit for foundation work to correct the problem (across the entire house), with the project likely completed by the end of 2020. Given that we are planning on foundation work, which may affect the relative height of different portions of the house, I wanted to ask:
1) is there a viable short term solution to this problem? I was thinking of re-grouting the inside of the shower to prevent further water intrusions
2) if re-grouting is an option, what might be the best material to use? There is a range of the gap widths (1/8 to 1/4"), with some sections poorly fixed with what appears to be caulk
3) is it better to delay any remodeling work (for long-term fix) to later when the foundation work has been completed?
I've included a couple of links to posts that discuss related problems, including best practices in re-grouting showers and a discussion of water damage.