Help.... The dreaded 6mm ply

[mbcmultitrade]

I have just tiled a bathroom floor which comprised of 6mm ply, over t&g chipboard flooring, - which then had an UFH coil taped to the ply. I reluctantly tiled onto the ply and consequently the adhesive has failed. The griut has cracked and there is movement on the corners of the tiles (60x30)
I was sure there was no real deflection in the original floor, and I assumed tiling onto the 6mm ply would be sufficient, despite hearing the odd horror story re the dreaded 6 mm ply.

Yes - I was wrong.

Can someone explain to me why you should not tile onto 6mm ply and how/why it fails the tiles/adhesive.

Also. Moving forward, Can I now remove the tiles and use a flexible SLC on top and then re-tile, or do I have to rip up the ply & UFH and start again with Hardi backer?

Your advice and 'told you so's' greatly appreciated.

P.s
I used Nicobond Quick flex ady and primed the ply twice with Nicobond acrylic primer.

 

[DHTiling]

Not a tiler then. Typical multitrade doing something he knows nowt about. Then comes and asks why . Ye ha ride em cowboy.

Angers me when peeps tile and oh it has failed.

 

[demi34]

You tile on top sugar paper

 

[Concrete guy]

Fundamentally, there was too much movement (flexing) in the substrate as it hadn't been reinforced sufficiently.

That really is the top and bottom of it.

A thicker ply or suitable backer board screwed down would have reduced movement, cracking, flexing.

There are some that would also incorporate an uncoupling membrane such as Ditra Matting on top of the reinforcement. On a small bathroom floor I feel that's overkill - but some tilers will require it.

 

[The D]

I would rip it all up and employ a tiler to do it right. That is the best advice I can give you

 

[Brian the Tile]

im sorry but you might as well have put cardboard down,you are right you will have to take the flack now ,why not stick to what you know ,whatever that may be hopefully you will now have learnt a lesson ,that is we are called TILERS because that is what we do ,maybe lesson learned hopefully, rant over :mad2:

 

[cam_low]

Multitrade = jack of all master of none aka cowboy

good on ya taking the hit though, least you haven't ran a mile like most cowboys do

 

[bugs183]

It could have been worse MB, you could have said you used PVA, tubbed tile on to wood adhesive, lash clips and you turned the heating on to dry out the adhesive! Well done for putting hands up though!
Yea matey as the guys say it needs all ripping up, no amount of flexible adhesive will absorb any deflection in the timber.

 

[Brian the Tile]

and a big :hurray: for being brave enough to accept that you made a mess of it,if you need advice,go ahead and ask first we dont bite ,honest

 

[widler]

and a big :hurray: for being brave enough to accept that you made a mess of it,if you need advice,go ahead and ask first we dont bite ,honest

he has asked for advice,and everyone bit bri

 

[Mr T]

shouldnt you use flexi adhesive on any wooden substrate?

 

[mattle40]

And bit hard lol

 

[mattle40]

shouldnt you use flexi adhesive on any wooden substrate?

I suppose the term "flexible" is a bit misleading, yes you always use flexi on a timber substrate but don't take the term so literal. you can't tile a bouncy castle with it

 

[Mr T]

tbh it dries rock hard so i guess the term 'flexible' should be... a tiny bit more flexible than the norm lol

 

[DHTiling]

tbh it dries rock hard so i guess the term 'flexible' should be... a tiny bit more flexible than the norm lol

Are we talking C2 or S1 or even S2 adhesives..? ... what about a good old Elastomeric crumb adhesive..