what is underneath the tile?waterproof-wise?

And inside the shower where the walls meet the floor, I don't see any type of caulking. (grout should not go where two joints meet. ditto for the shower walls). There needs to be a shower caulking in the same grout color used for that.

I don't have a lot of waterproofing knowledge, so I will comment to bump. I am concerned with the efflorescence in the side tiles. And, all the grout gaps in your photos.

I think you are right and wise to note that discoloration now.

Thanks everyone.

Yes, I am concerned by the white in the tiles as well. I saw him put waterproof layers underneath when he was installing shower.

Could this leak be from the shower door joints? This is what he is telling me - that the installer didn't silicon the joints in the drilled holes?

Is the top of the curb supposed to be slanted in this type of shower because ours is flat? Water tends to pool here.

I have attached a photo showing where shower floor meets curb inside shower. This was originally just grout originally that cracked and came out in pieces but now has grout and silicon after he redid it.

There is movement in the floor or substrate causing tile joints to crack allowing water in. The curb could also be problem and the way it was constructed.

Best way to handle this is to take this apart and investigate further and pinpoint the problem before substrate will start to deteriorate causing a more serious damage.

Pull the doors, demo the tile, waterproof, and have a solid surface curb (sides, ends, and top) with a pitched overhanging top with a drip slot fabricated and installed. Reinstall the doors without penetrating the waterproofing. Never gonna leak.

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