Weird shadow mark

[martin88]

Hi all,

We had our kitchen tiles roughly 10 days ago with white 600 x 600 porcelain tiles, we have Electric UFH, I wait the 7 days before turning it on. I notice last night there we have some form of dark shadows appearing on the tiles. It can’t be a leak as we have no pipework in the floor.

I’m not sure what this could be. Will
It go or will I have to break out the effected tiles?

 

[blup]

Some possibilities...

It could be either a defect in the tile, or 7 days was not sufficient for the adhesive to go off, and this has somehow allowed damp through the microporous underside of the tile, in turn affecting the appearance of the top face.

It could be left a little longer to see if other tiles are affected and replace them as necessary.

Blup