Tile on tile question, again!

[maf20]

I'm refitting my bathroom, with the help of a builder.

Tomorrow, we're due to start the tiling. I'm using a Travertine tile, 600m in length. We are planning to tile on top of the existing tiles. I have checked, and the existing tiles are very firmly in place, and the majority of the wall space is on external walls.

However, one thing I hadn't considered, until reading up on it now, was the weight on the walls. These tiles are canny heavy! I did have a very reputable tiler look at it, and he said it's no problem.

Any thoughts?

Also keen to hear thoughts on wether or not walls should be primed.

Thanks

 

[tpt]

i think your going to struggle on two counts. first is the weight, as you have already found. if the existing tiles are on plaster then your a very long way over the top weight.

The second is adhesive, you'll need to be using a white powdered adhesive for trav and you may struggle to find one thats suitable for tiling over tiles

 

[Karis]

I would advise you bite the bullet & remove the old tiles. Although sometimes unavoidable, tile over tile is a bodge at the best of times.

As already posted, your may experience several problems. Trav tiles that size are going to be heavy enough on their own & if you add on the weight of the original tiles, your almost certainly going to be way OTT of maximum permissible weight if it’s plaster (20 kg/sqm including adhesive & grout). Big risk the lot will end up on the floor before too long, including the original tiles & plaster. Large tiles need a very flat tile base & if the original tiles aren’t perfectly flat, the new travs won’t be level & look awful. Finding an adhesive for suitable for absorbent trav over glazed tiles which is fast setting & white. The biggest problem your likely to have is keeping the tiles in position while the adhesive sets enough to support the weight of the tile. The tiles will also need suitably prepping by applying a slurry bonding coat.