QUESTIONWe had tile installed in our bathroom shower about 6 years ago. Not sure when I noticed this- probably at least a couple years ago- but some of the tiles are becoming discolored around the grout lines. It is very faint and looks like a bluish color bleeding into the tiles. The grout is a tan color and the tiles are 6 inch white subway tiles. Is moisture getting behind the tiles? Why is this happening and is there any fix? I can send a picture if that will help. Thank you!!
ANSWERAnswer - If you have subway tiles, I assume you are talking about tiles on the walls of the shower. Although perhaps you did install the subway tiles on the shower floor.
Most subway tiles are glazed tiles over a porous body. So water that gets in the grout joints can migrate into the tile body. Normally the glaze on the tile surface isn't translucent, but sometimes it does have a slight degree of transparency.
The bluish color could be just a wet condition. It could be microbial growth. It could be a stain from some product used in the shower.
If it is on the shower floor, then more likely it could be that the shower pan weep holes at the drain are plugged because of how it was installed and that water isn't able to fully drain away so it stays wet.
A glaze tile has a glass-like coating on the surface and is typically impervious. So if the stain is in the tile body then you can't clean it from the surface of the tile. The poultices that are normally used to remove stains in natural stone. You could try using that type of product to see if you can remove the stain. You can go to the resource section of our website and go into the Cleaner and Sealer page to see some of the manufacturers who provide various types of cleaners and sealers.
Keep in mind that you by cleaning the tile and removing the stain might no remove the problem as you will only be treating the symptom of the problem.