Cracked ceramic floor tiles, from ladder?

[Peter W]

Hi,

I've not long been tiling long and have recently tiled a bathroom floor but the ceramic tiles have cracked. I used Bal flexible floor ahdesive (10mm notched trowel) and Bal Superflex floor grout.

I took up the floorboards before tiling and put down WBP 18mm ply and also screwed many batons in between the joists (nice and flush with the joists at the top edge) and screwed the ply down every 200 mm at least. I thought i was doing a thorough job.

I can't understand how they've cracked as it was a very solid prep.

The customer used a step ladder and took some heavy stuff out the loft a cple of weeks after completion of the job. Could it have been this? Should they have put the ladder on a spreader board first?

Or is it likely to have been the towel rail pipes under the floor causing contraction / expansion?

The ply was put down in approx 4ft square pieces for ease if handling, and the cracks seem to be above where these ply boards meet. Several have cracked and the cracks are pretty much in a straight line.

Be great to hear your ideas as i don't want to do another before i know what to do in future.

Cheers,


Pete

 

[MICK the Tiler]

What size and what type of tile Pete?

 

[Peter W]

They were a ceramic floor tile from B&Q. From memory they were called Decona, were 8 mm thick and were 330 x 330. I think...

 

[Turkish]

Did you leave a small gap between the ply when you laid it? If not is it possible the boards have expanded and pushed against eachother? Apart from that i can`t see what i would have done differently which is worrying!

Turkish:huh2:

 

[Peter W]

Hi Turkish, thanks for your reply, i didn't purposely leave a gap. I know that some of them inevitably had about a 2mm gap in between them just from my own (probably poor) tolerances.

Perhaps you're right, i didn't think of leaving a gap when i was laying the ply, i thought at the time it would be better to have them nice and flush, but now thinking about it....

 

[DHTiling]

Even though you prepped the floor with extra noggins and used used 18mm ply doesn't say that you could not be getting deflection in the joists themselves and seen as the joins in the ply is the week spot this will explain why they have cracked there.......did you also check you were getting good coverage with the adhesive..?...

 

[Peter W]

Yes i was getting very good coverage. In respect of getting good coverage i found it was easier tiling the floor than the walls i've done as the ply was so nice and flat.

Is it possible for ladders to damage tiled floors anyone?

 

[Gazzer]

I feel the only way a step ladder would damage tiles is if the tiles hadnt been fixed properly. As you feel there were bedded in correctly i would eliminate the cause of the problem being the step ladders.

 

[Peter W]

Thanks for all of your responses guys, it's all very helpful and is great to get a second opinion.

Any other info / ideas / suggestions would be welcomely received.

Cheers,


Pete

 

[cam_low]

Did this ever get sorted ? What was the outcome ?

 

[Daveyboy]

Hi Pete, not a nice situation to be in....it's not clear from yr post where the ply joints meet in relation to the run of the joists and extra noggins you put in...If the joints are straddling a joist and the cracking is running the same direction as the joists, then it could well be too much movement in the joist(s) or settlement of the property. If the joints are at right angles to the joists, then it could still be joist movement if the crack line is also at right angles.

I've never had a problem with the ply swelling up/shrinking but that could happen if the ply was damp/too dry when laid. I had an ensuite (above a garage) suffer a bit of settlement and it split a 3m row of tiles straight down the middle of every tile in that row! The rest of the room was undamaged.

I also always check to see how much 'bounce' a floor has before agreeing to tile it, particularly in older properties where the joists are likely to have come loose in their wall mounts or rotted slightly. If your floor had too much bounce, then the moving of heavy objects over/on it would increase the risk of cracking.

Good luck sorting it out....David

 

[crazysteve123]

Be careful of dust if you have to remove the tiles and grout, it can fill a house trust me i know, especially if you need to use a grinder seal the door off if you can and take your time its very easy to chip the other tiles..

 

[Highlander]

One possible problem is that alot of B&Q tiles are crap and soft and the stepladder could have been close to the edge of the tile. Otherwise could be deflection.

Highlander