Tiling onto chipboard?

[weirdfish]

Am I right in thinking that it's not advisable to tile directly onto chipboard, this is in the en-suite, and it looks like the water resistant type, ( slightly green in colour ).
The old tiles were stuck onto thin ply, but I had to take that up due to the amount of adhesive that was left on it, I suppose that might be giving me my answer, but just thought I'd ask in case things were different now, especially with new products.
The other reason is that we want to put down slightly thicker tiles, and it would create a very slight step if ply is required.

 

[Old Mod]

If u have room, glue and screw 6mm Hardibacker, simplist solution.
Prime floor, follow adhesive manufacturers recommendation
Stick down with same adhesive as you're going to use on floor.
Overlap joints beneath. Stagger joints on Hardie. Screw down and countersink screw heads.
Don't use Hardie screws, something like Turbo gold screws from screwfix.
Tape Hardie joints with a scrim tape, cover tape with tight skim of tile adhesive.

 

[weirdfish]

I did notice that product, but at 6mm it would create a real awkward step, if I have to overply, can I get away with 3mm ply, that way the difference in levels between bedroom and en-suite wouldn't be that bad.

 

[Old Mod]

Ply isn't a suitable product, it's still subject to expansion and contraction due to heat or moisture. The whole idea of using an inert material like Hardie is that these external forces will have no effect, thus giving u a stable substrate to tile to!

 

[Old Mod]

U could maybe use a little self leveller outside bathroom to lift carpet a few mm

 

[AliGage]

3mm ply will be as much use as wet newspaper.
Hardie us 6mm. A difference if 3mm to what your proposing. It's hardly a step.

 

[Dan]

A slight step with a good quality door transition is nothing these days. Can get over 20mm easily enough and not ever trip etc.

 

[mark1966]

Dittra mat stuck down with vs 45

 

[AliGage]

Dittra mat stuck down with vs 45

I've never understood why people choose ditra over timber instead of a backer.

 

[Ian]

I've never understood why people choose ditra over timber instead of a backer.

I've seen a couple of failed floors recently where ditra was used directly over chip board, granted I don't know what adhesive was used but, they had failed none the less. Only small bathroom floors, 3m max.

 

[Old Mod]

I've seen a couple of failed floors recently where ditra was used directly over chip board, granted I don't know what adhesive was used but, they had failed none the less. Only small bathroom floors, 3m max.

This is one of the points raised when I spoke with @Glynn yesterday,
TM prefer use of board in these situations over decoupler.

 

[AliGage]

I've seen a couple of failed floors recently where ditra was used directly over chip board, granted I don't know what adhesive was used but, they had failed none the less. Only small bathroom floors, 3m max.

This is one of the points raised when I spoke with @Glynn yesterday,
TM prefer use of board in these situations over decoupler.

This was atopic I was leading into with my polypipe UFH post a few weeks back.

I don't know if it's people not understanding it's actual usage, or maybe being misinformed. But it's for lateral movement not defection. (not that I'm saying a backer is)
If the chipboard still has bounce then ditra is money down the drain.

Small pun there.

What was the reason/symptoms of failure on the one you looked at @Bri?

 

[Old Mod]

This was atopic I was leading into with my polypipe UFH post a few weeks back.
@Bri?

Praps u should bump it! 🙄

 

[AliGage]

Praps u should bump it! 🙄

You gonna make me go look!? *huff*

 

[Old Mod]

You gonna make me go look!? *huff*

Well I'm not! Haha
What u think cos I'm a mod I got special search powers? Haha
I got the same crystal balls as u mate! Haha

 

[AliGage]

I can't find it

 

[Old Mod]

I can5 find it

Hahaha
God ur lazy!

Water UFH - Polypipe (Fixed Overlay) UFH

 

[AliGage]

😀

 

[Ian]

This was atopic I was leading into with my polypipe UFH post a few weeks back.

I don't know if it's people not understanding it's actual usage, or maybe being misinformed. But it's for lateral movement not defection. (not that I'm saying a backer is)
If the chipboard still has bounce then ditra is money down the drain.

Small pun there.

What was the reason/symptoms of failure on the one you looked at @Bri?

Deflection, chipboard was just nailed to the joists and had worked loose over a short period of time, most of the grout had either hairline cracks or had big chunks missing.

 

[Sean Kelly]

I've used Ditra before on a bathroom floor 2.5sqm. no deflection and screwed down. Ditra, rapid set flex and rolled using an amtico roller. I would only ever do this is a very small area where there is not much foot traffic.

 

[AliGage]

Deflection, chipboard was just nailed to the joists and had worked loose over a short period of time, most of the grout had either hairline cracks or had big chunks missing.

Deflection, exactly. No amount of ditra would of helped. Had a backer been used instead the likelihood is that by glueing and screwing them in would of provided enough stability for the floor to be tiled.

Ditra over chipboard doesn't get you away from the fact that chipboard is a load of tosh in the first place.

Timber floor, backerboard
SLC, screed, stone or anything heated. Ditra