Grouting cracking on floor despite being grouted twice

[platforminc]

I have recentlty had a tiling job done on a flat on second floor, its a victorian conversion flat, Linyl flooring was laid before. and it was moving slightly and the floor bumping up too, so I decided to tile it. Now what happened was that during the process, the old flooring got taken out i.e Linyl, a think layer of plywood and a foamy like material which I believe is for noise insulation.

On came 9mm ply screwed to the ground, and tiles laid on it, what seems to be happening is that as soon as grouting is laid, and starts to dry it begins to crack. Now I must admit, I dont believe the ply on the floor is 100% strong. As I can still feel a little tiny movement, but not significantly much.

A few things/thoughts.

Coould it be that the grouting used isnt the flexible and thus causing this problem.
Mesh wasnt lasd on the floor before the tiles went on it.
At the start of the job, the wrong type of glue was used, they used wall for parts of the kitchen before the floor glue was bought.

Any ideas here on what can be done.

I have included pictures of the old flooring and also the new tiled one as well, the picture looks like its laminate as in the old flooring but its linyl.

New floor

Untitled

• platforminc
• 3 Apr 2012
• 1

Old floor

 

[Lower]

Any movement in the floor means that the grout and possibly the tiles will crack.

9mm ply isn't thick enough.

Has the tiler used a quality flexible adhesive and a quality, flexible grout?

When i did my bathroom i replaced the existing floorboards with 25mm WBP ply and used the appropriate adhesive and grout. There were no cracking issues.

 

[platforminc]

Any movement in the floor means that the grout and possibly the tiles will crack.

9mm ply isn't thick enough.

Has the tiler used a quality flexible adhesive and a quality, flexible grout?

When i did my bathroom i replaced the existing floorboards with 25mm WBP ply and used the appropriate adhesive and grout. There were no cracking issues.

Thanks for the reply, really appreciated.

The reason 9mm was used was because anything higher will lift the floor higher than the adjoining part of the flat, living room for kitchen and hallway for the bathroom.

Flexible adhesive wasnt used, just the normal one which requires that the floor be very hard. In this case its clearly not.

Adhesive is quality one from wickes.

Now my dilemna is that, we can regrout using flexible grout and see what happens or bite the bullet and take out the whole thing, tiles and ply and relay another ply or possibly go another layer deeper and take out the board, then I will be able to use a board more than 9mm thick, lay metal mesh and then tile on it. The building is old and not the strongest. Now the second option is what an experienced builder proposed when he had a look yesterday. The downside is that I have lost £500 down the drain and have to spend another £500 again.

Any thoughts. The tiles are not broken at all, floor has only been laid for 3 weeks. I dont know whats going to happen in future to the floor.

 

[prceramics]

the comment "Adhesive is quality one from wickes" worry's me not sure they sell any !
You could try the regrout with flexi grout like the bal superflex and hope for the best in my opinion you should of used tile backerboard instead of ply and as mentioned a quality trade floor flexy adhesive ultra, bal, or mapei to mention just a few even topps own brand stuff would of been better it's made by palace. Good luck

 

[Lower]

Unless you can take all or the majority of the flex out of the floor you're going to have problems in time, even with proper flexible adhesive and grout. Any movement is going to break the bond between the rigid tiles and the floor or crack the tile if the bond doesn't break.

You may as well have a go with flexible grout and see what happens. You might get a year or two out of the floor at which point you would then have to do it properly. But at least then you'll know it definitely needs doing.

I don't know where the metal mesh thing comes from though. As already stated, tile backer board would be much more appropriate or straight onto 18 or 25mm WBP ply.

Sounds like you need to get a tiler that knows what they are doing involved and you may have some recourse to the person that tiled you floor so badly in the first place.

 

[platforminc]

Thanks very much for the reply. If it were you, what will you do as per the floor, on one hand I am tempted to just bite the bullet and destroy the whole floor and do it over again, on another hand I want to be pragmatic. What I noticed is that some part of the floor is strong and some other parts arent so strong perhaps. We will use the Bal flexi grout and then see what happens. Looks like the guy just has no clue, even told me to buy PVA glue after tiles have already been laid. So I guess what he wants to do is pour PVA in the grouting spacing and hope for the best.