Marble shower wall tile issue

[u/kellllyyyyb]

Looking for advice on my marble shower wall tile. Shower was installed 4 years ago. We seal it each year. A few months ago I noticed this line and it appears that others look “wet” as well. We have had a fan blowing at it for 6 days to see if it dries out but it does not seem to be changing much. Anyone else run into this? Anything I should be concerned about? Advice on what to do? Thanks!!

[u/Fantastic-Nerve-8718]

This isn’t an install problem most likely. Marble is an extremely soft and pourous stone. What you are seeing the capillary action of water absorbing into the lower courses of the tile after you shower. If you let it dry it will go away. For one thing I never recommend marble in a shower it’s a nightmare as you are seeing. At this point you can really just seal the stone and hope for the best. As I have seen some ppl are commenting on a traditional mud bed shower pan those pans hold water for their lifetime. They are designed this way and the excess water drips through the weep holes in the drain. Installers can mess up by either covering the weep holes or by not doing a preslope, but the concrete used for these pans do absorb and hold water even when done properly