Problems with tiling over tiles

[PeterH]

Hi,

I'm after some advice from professional tilers after encountering problems with the new house I bought new from developers just over 2 years ago.

I noticed some rust coloured stains on the mosaic strip in my bath/shower. I sprayed with flash and scrubbed lightly with a nail brush and away came the stain and all of the grout too (albeit only in patches). I dug out all of the loose grout/adhesive with a small screwdriver and a few of the mosaics were loose and came out. There was a "mush" behind which came off easily to reveal another set of tiles behind.

What I think may have happened is that a previous purchaser had wanted the tiles changing so where the developer could, he just tiled over. I think that mosaic which includes alternate squares and metal faced circles let water in behind the metal circles.

I'm interested in opinions as to whether:

a) these metalic circles are prone to problems;
b) tiling over tiles is an acceptable professional standard for a brand new house;

Clearly I am concerned that I am going to have similar problems with the large tiles next and indeed if I'll have the same problem in the other batchroom.

Any opinions would be gratefully received.

Regards

Pete

 

[Bubblecraft]

Hi & welcome to TF

 

[White Room]

Hi and welcome....tile over tile is not really recommended, the mush could be a tubbed adhesive which softens when in contact with water which I've found most contractors tends to supply.

 

[ifindoubtgrout]

theres a chance the extra tiles ar just behind mosiacs, to help make them flush with main tiles.

 

[AMtek]

Ifindoubt could be right and they have used thin tiles to bring the mosaics flush with the other tiles but i would say that if the water ingress is that bad behing the mosaics the adhesive behind the other tiles is likely to be much the same. Rip out and re do for me