Cracked floor tiles - normal settling?

liamo

Hi,

We have just had an extension built and moved back in about 6 weeks ago.

The downstairs area of the extension is a kitchen/dining area and we have had it tiled with big 60x60cm tiles. The surface being tiled was joists topped with large boards.

Yesterday, having heard a few very loud cracks I discovered that 4 of the tiles have cracked. The cracks run in a straight line through the 4 tiles.

I expect some settling to occur and expect to have to touch-up some plaster and paint work but wasn't expecting this! We got the best adhesive available for tiling on boards.

Is this normal? Do I need to have this checked out in case there's a problem that could get worse? Does the builder bear any resposibility for this or is this just one of those things? I'd appreciate any opinions.

Regards,

Liam

reilig

liamo wrote: »

Hi,

We have just had an extension built and moved back in about 6 weeks ago.

The downstairs area of the extension is a kitchen/dining area and we have had it tiled with big 60x60cm tiles. The surface being tiled was joists topped with large boards.

Yesterday, having heard a few very loud cracks I discovered that 4 of the tiles have cracked. The cracks run in a straight line through the 4 tiles.

I expect some settling to occur and expect to have to touch-up some plaster and paint work but wasn't expecting this! We got the best adhesive available for tiling on boards.

Is this normal? Do I need to have this checked out in case there's a problem that could get worse? Does the builder bear any resposibility for this or is this just one of those things? I'd appreciate any opinions.

Regards,

Liam

Are you sure you used flexible adhesive for tiling on the wood? Wood can expand and contract with teh heating of the house and if the adhesive does not move with the wood, the tiles are likely to crack. Doesn't matter if you got the best or worst adhesive available, it it's not flexible adhesive then you have a problem.

liamo

reilig wrote: »

Are you sure you used flexible adhesive for tiling on the wood? Wood can expand and contract with teh heating of the house and if the adhesive does not move with the wood, the tiles are likely to crack. Doesn't matter if you got the best or worst adhesive available, it it's not flexible adhesive then you have a problem.

Hi reilig,

Thanks for the comment. Yes, got flexible adhesive specifically for tiling onto wood.

muffler

Timber joists if not properly dried can twist ad warp a bit with the drying out process. Maybe check where exactly the cracked tiles are. You are going to have to lift them so its worth taking a note if the crack occured directly above the joint in the plywood flooring - I assume it was marine grade ply or the likes that was used.

Where are your underfloor heating pipes in relation to the cracked tiles?

witnessmenow

How large of an area is it?

Also just for future reference, there is a product made by company from the UK, Dural, that is an anti-crack matting. The attached file should explain a bit about it.

And before anyone asks, i dont work for dural, or am i an agent for them or anything. I work for a flooring contractor/tile shop and we use that product quite regularly

liamo

@muffler: I was beginning to think along the lines of the joists drying out and possibly flexing with temperature changes (it was a *really* cold night). As you suggest, I will check when I lift the tiles if it's along a joint in the plywood flooring and where the piping is in relation to the crack. From memory, the crack certainly seems close to where I think a joint would be and it's going in the right direction.

I was advised not to bother lifting the tiles for another 6 months or so to let any additional settling take place. As for the quality of the flooring - I don't know, but I'm certainly going to put the question to the builder.

@witnessmenow: It's a funny shape but the main area (where the crack is) is about 16ft x 12ft and the crack crosses 4 tiles (circa 8 ft). It's a pity I hadn't heard of that Dural matting before but I will certainly remember it for future reference, thanks.