Looks like moisture in the wall behind the tile. What material is the tile?

Also what is the material on the outside of the home?

Condensation will probably figure in the answer. How is your exterior wall structured and what is the tile material?

The tiles are glass tiles. I also thought it was moisture but why parts of the tiles not all. I also did a hair drier test but didn't change anything. The shower was only used once and have not been used since but no changes in the issue. Outside of the house is stucco.

This is just a guess but could it be that the tile setter used mortar that reacted with the backing on the back of the glass tile? I glass tile I am familiar with is clear and the color comes from a film attached to the backside of the tile.

He is coming over this Saturday and have a look. It is weird that the other two wall to each side of this one, the tiles are UNAFFECTED...Also, 3-4 tiles down, these tiles are perfect. I attached more photos for you guys. Each wall and 3 tiles down from the affected ones.

RIGHT SIDE of the AFFECTED WALL

3 tiles down below of the affected WALL TILES (1)

3 tiles down below of the affected WALL TILES (2)

LEFT SIDE OF THE AFFECTED WALL

definitely call the installer and demand that they inspect & fix. they must have done something wrong.

those glass tiles are gorgeous, by the way. nice choice!

that is so bizarre. it has to have something to do with the tiles being on an outside wall but I haven't a clue as to what or why

It could also be thermal expansion and contraction pulling the backing off. Just a wild guess.

What a beautiful bathroom!! I hope that you can get some resolution to the problem.

@ Classic Structures Inc. - so for my information and edification, if it is thermal expansion and contraction, how can that be avoided?

That is a great question! Is the tile attached directly to a slump block, adobe brick or regular brick wall or is it attached to tile backerboard over an insulated wood framed wall? Or something else?

@ Classic Structures Inc - attached to backerboard over an insulated wood framed wall

Is the backerboard waterproofed with a paint-on product, or is there sheet waterproofing between the backerboard and the wooden studs? If it is waterproofed, why would there be any condensation behind the tile?

Could it also be a case of spot application of thinset on the back of the tile? It looks like how some amateur tilers apply thinset when back-buttering.

Thanks Nancy for your input. I'm leaning towards the thermal expansion and contraction by Classic Structures Inc. on why this happened. In any case, it will be a good piece of information for my tiler as well as he has not seen something like this before. If he has to redo, he would need to just replace that wall of tiles....I hope!

If this is not "a problem" known to others with houses constructed similarly to yours in your climate, though, there is something wrong with the materials or application.

Noel,

It should not be an expansion contraction issue if it is over a wood framed wall. Defective tile backing or mortar is my guess.

Thank You All! To make the long story short the bathroom turned out wonderfully, redone by the contractor. Unfortunately, someone had to lose his job.

Don't leave us hanging! What was done wrong?