uncoupling membrane between limestone tiles and chipboard flooring

[Daveyboy]

Hi guys...went to look at a job today, house refurb/extension..100m2 of 600x400 limestone tiles on solid floor over seven joining rooms (ground floor) and three ensuites with chipboard flooring (first floor)..Normally, I would lay 12mm plywood onto the ensuite floors (approx 3.5m2 each) then tile onto that but in this case I can't because the height change hasn't been allowed for and because the previous tiler who has been sacked (they call him lippy for obvious reasons) has already tiled the bathroom...it looks like he has tiled straight onto the chipboard but the main builder assures the client he primed the chipboard then laid a matting down then tiled onto that...

I've used the impey membrane and the dura WP matting before but never directly onto chipboard...

Is the impey membrane suitable to apply directly onto chipboard after it has been primed?

Is dura WP suitable given the small areas and if so, what flexi adhesive is suitable to use on chipboard?

Is there another product(s) I should use?

The client looks worn out from the building work and stress from the previous tilers' work, and I'd rather not add to it by using the wrong material.

 

[brian c]

PERSONALLY I WOULDNT AND DONT THINK ITS RECOMMENDED.wHY NOT USE 6MM HARDIEBACKER THEN MEMBRANE?or 9mm ply and 2 part flexi or hardie and 2 part flexi.

 

[Daveyboy]

Hi Brian..the previous tiler has not left any allowance for any type of boarding to be laid between the chipboard and the tile...

I personally don't think he has used a membrane as I couldn't see it at the door threshold where the tiles stop..but I want to find out if I can use an uncoupling membrane on chipboard before I give the client the bad news...

 

[brian c]

im sure it will need over boarding first,due to debonding of adhesive from the chipboard.

 

[brian c]

I have just read the spec again and it says that as long as the substrate can take the weight of the tiled area and it is sound enough then it can be used directly over chipboard and plywood.
As long as the substrate is capable of taking the weight of the tiled surface, Schlüter-DITRA can be applied directly to any existing timber -- including plywood and chipboard.

And even in older properties with butted planks, small gaps of around two millimetres between the joints can be successfully bridged with membranes such as Schlüter-DITRA without the need for fillers.








have a read at this....http://www.schluter.co.uk/2808.aspx

 

[tfs]

Hi Daveyboy,

Based on what Brian has just said I would ask the Joiner or builder to cut out the chipboard floor and add some extra noggings (Dwangs as we call them in Scotland) to ensure as close to zero deflection as possible and then he can put the chipboard back down screwed into the dwangs. Then install the matting.

 

[Daveyboy]

Cheers Brian..that's good news..now all I need is an adhesive to secure the ditra mat to the chipboard...

 

[brian c]

I was thinking maybe kerraquick and the latex additive?

 

[White Room]

Can't you use a vinyl adhesive for ditra, one local shop to me does one and schluter also supply there own make

 

[brian c]

Hi Daveyboy,

Based on what Brian has just said I would ask the Joiner or builder to cut out the chipboard floor and add some extra noggings (Dwangs as we call them in Scotland) to ensure as close to zero deflection as possible and then he can put the chipboard back down screwed into the dwangs. Then install the matting.

This is also a good option for you.

 

[tfs]

Im not 100% sure but If using a vynil adhesive it may need to be an acrylic adhesive

 

[tfs]

I remember ooking through some literature I got from Ardex and they reccomended one of there adhesives for Ditra matting. I will have a quick look to see if I can find this.

 

[Daveyboy]

Can't you use a vinyl adhesive for ditra, one local shop to me does one and schluter also supply there own make

Thanks Whitebeam..I have e-mailed the techinal guys at schluter to see if they can advise a suitable product..at the moment, their information on their website does not specify any particular product...

 

[tfs]

Found it! 'Ardex AF 200' for adhering ditra matting onto timber floors

 

[White Room]

ARDEX AF 200 from ARDEX UK

 

[Perry]

i have put pesalastic on a chipboard floor but it was 40mm on thick on steel joists at 300 centres i wouldn't try it or the customer would be even more stressed when it started cracking

 

[Daveyboy]

ARDEX AF 200 from ARDEX UK

Every time I try the above link my internet explorer crashes..even tried going direct to www address but the same happens..will try it tomorrow...

 

[White Room]

Try this on Davy Broken Link Removed

 

[Daveyboy]

Try this on Davy Broken Link Removed

Cheers Whitebeam, Shulter have come back recommending Ardex as well so just need to get some costs from a nearby CDT...thanks again everyone

 

[Sutwam]

Hi

AF 200 or equivalent is perfect for sticking Ditra and CI Matting down. I have been to Ardex and seen this technic being used, Ardex call it a double drop method. A quick call to Ardex technical would give you full info on this method.

Both CI and Ditra are 3mm thick so its a lot thinner than the boards, and is perfect for taking the movement in the horizontal plan, but if there is any bounce in the floor that would need to be sorted before using any matting.