Dark blotches on tiles

[jamie Smith]

Morning all. I have searched the forums and can't seem to find an exact match for this problem

I have recently laid ceramic tiles in my bathroom with undertile heating. I connected up last night and all was fine until the surface of the tiles started to show dark blotches where there are hollow spots (I know there shouldn’t be, but I don’t know how they got there). It’s happened before when they got wet, but it went away after a couple of days.

Any ideas lads?

 

[nellyb]

Jamie, what sort of tile are they? I know you say ceramic, but are you sure they aren't a light coloured natural stone such as travertine or limestone? If they were and used a grey adhesive as opposed to a white one, it could be the adhesive shadowing through.

The only other thing I can think it might be is that the tile adhesive has absorbed into the biscuit/body of the tile if it is ceramic or possibly porcelain and not dried out properly yet. If this is the case, then it may well just disappear when it is properly dry.

Other than that, I haven't got a clue!

 

[jamie Smith]

Nelly, you could well be right. Now that the heating has been on for almost a week, the patches appear to have dried out and faded. It looked so bad for the first few days, I had visions of me having to rip them up!

Here's hoping they don't come back!

 

[Moz]

nellyb
your right the the job mix hadnt gone off .. an was "blushing"