we have just had a bathroom floor tiled but after a couple of days the grout has started to break up and crack anyone have any ideas why and how to remedy it? ???

most likely wrong grout and wrong adhesive.

I recomend Flexable adhesive for all bathroom locations. Is it a solid floor? or Timber Floor? If it is upstairs then I would guess a timber floor, with floor boards? If this is the case was Ply or Chipboard layed first, over the floor boards, prior to laying tiles? This is a MUST - ideally at least 9 mm thick should be used.

Without knowing the precise "structure" of your floor it is difficult to accurately comment, but hopefully this will help.

Sounds as if the tiles have been laid on top of floor boards. Although as previously said it could be poor grouting. You can use a matting to put on top of the boards before tiling, this is the method I use. Check with the 'tiler' to see how the tiling has been done. Then you can make a decision on what to do next.

yes it was laid on floorboards with a sheet of thin ply which I think is the problem,it was put down by a ?tradesperson? it now looks like the whole floor will have to be taken out and done again! beware of so called experts!!!

I would wonder how stable the underlayment was prior to installing the tiles. You should have about 1" of total wood flooring prior to tiling. Also there are some adhesives you can mix with the grout to make it seal more firmly.

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MJDonovan

some grouts are more waterproof than others. worth checking what you use when you have the floor re-done.

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