Bal Adhesives - Tile Advice

[WillCalderwood]

I just had a chat with the Bal technical guys asking about priming ply, he asked what we were doing, which is:
Porcelain floor tiles on 18mm ply on joists at 300 centers. Large ceramic wall tiles on 18mm ply. I said we were going to use Rapidset Flexible. His response was 'You can't do that, that wont work'. He then asked all the details, and said we should be using Mosaic Fix on the walls and Single Part Flexi on the floor. No priming required. That was our only option.

I'm sure Bal know their stuff, however, I doubt their technical team are tiling with it every day in real world situations. What do tilers think? I've read elsewhere about using SBR bond on ply. Also, decoupling membrane, yay or nay?

Cheers

 

[Gazzer]

Ply needs to be primed back and edges.

 

[The D]

I do not tile on to ply at all walls or floors.

 

[area tiling]

I'd be priming the plywood , no need for mosaic fix on walls , think their just trying to make a sale on mosaic fix which no one really uses anyway!

 

[peteablard]

No need to prime the face of the ply just back and edges as mentioned above. I've done it with rapid set flexi and not had a problem. Not a great surface to tile though and should be avoided if possible

 

[Andy Allen]

if you want the best bal adhesive for the job, then the bal tech is right, at the end of the day there going to recommend there best product, as would any other adhesive company...

 

[jonnyc]

I do not tile on to ply at all walls or floors.

Well I have not tiled directly to ply for at least 12 -15 years either.
My recommendation would be that ply is overboarded with dukkaboard or similar.
I just hate the idea of tiling on to plywood when there are so many alternatives theses days full stop.
hardibacker instead of plywood but the chippies hate theses boards.
but strangely I have a job specified by architect working for an architect client right now and they both seem happy with fixing straight on to ply. I can only give my best advice and crucially put a disclaimer in if they do not follow it .
In the climate we are in ,where true professionals are competing against other quotes that may seem attractive to a client , I am of the opinion that if they accept my disclaimer ,I will just tile the floor or wall. You may say that is not right and I agree but the rules have changed .
i am not a chancer but I am self taught and I have followed tiling practices And recommendations .
go back four to five years and I would not have even entertained the idea of taking on a job tiling on to plywood.

 

[Peter]

Would be using rubber crumb/fast flex on the floor myself.

 

[WillCalderwood]

Thanks for the feedback guys. I think we'll go with Bals advice. At least if it all goes wrong we've got someone to shout at then (As well as ourselves for using ply).

Question about cement boards. Can they be used for building a stud wall? Or are they normally just used as an overlay?

 

[Andy Allen]

yes they can....

 

[WillCalderwood]

I'm guessing with the density they're probably more sound proof than ply too?

 

[Time's Ran Out]

I'm guessing with the density they're probably more sound proof than ply too?

They don't accept moisture like plywood!
I'd cover all walls with hardi, and floors with a decoupler.