Tiling concrete floor and UF heating

[Spare Tool]

Ive fixed those un-coated boards a few times and never primed either side of em yet..just stick them with a wetter mix of adhesive making sure not to trap any air pockets under them. The problems here have come from trying to stick them to a floor that wasn't leveled over in the first place..

 

[The Tiler]

hi Andy
not looking for argument on the subject and maybe getting of topic as harry said, but why prime top and not bottom? Both are stuck with adhesive

 

[hmtiling]

hi Andy
not looking for argument on the subject and maybe getting of topic as harry said, but why prime top and not bottom? Both are stuck with adhesive

I wouldn't use them again but priming the top would help the ufh adhere properly and prevent any curling and also aid flow of levelling compound

 

[Dumbo]

I haven't found a background yet that priming is detrimental . No need to prime and do not under any circumstances prime are two different things. But i havent used those cheap uncoated boards

 

[The Tiler]

looks like I'm out number but will still prime both sides as I believe it should be, have seen how bad a S1 adhesive sticks to an unprimed surface and sadly not found another product I'm happy using for wet heat. As for electric I'd use a covered backer board.
looking forward to reading other posts and giving input if I think it will be of assistance, please be gentle with the newbe

 

[Andy Allen]

I haven't found a background yet that priming is detrimental . No need to prime and do not under any circumstances prime are two different things. But i havent used those cheap uncoated boards

Depends on the adhesive being used.
Some state do NOT prime cement boards or light weight backer boards...

 

[Dumbo]

Depends on the adhesive being used.
Some state do NOT prime cement boards or light weight backer boards...

I've had that before . One which springs to mind was bal saying that about ply ( not that I was tiling to ply ) but it was in a similar conversation to this . So rang them up and challenged them over it ( I particularly like challenging bal self proclaimed messiah's of tiling ) and their response was you can prime it if you want to without affecting performance .

 

[Steve01]

If nothing else please say they are porcelain tiles?

Yes polished porcelain - what difference does that make ?

 

[Andy Allen]

I've had that before . One which springs to mind was bal saying that about ply ( not that I was tiling to ply ) but it was in a similar conversation to this . So rang them up and challenged them over it ( I particularly like challenging bal self proclaimed messiah's of tiling ) and their response was you can prime it if you want to without affecting performance .

This is taken from there pdf, the adhesive is bal single part fast flex, an adhesive I use all the time on wooden substrates with cement boards...

 

[Dumbo]

Right if you look at next paragraph down that is what I challenged them on. Saying do not prime surfaces to be tiled on . I challenged them and they ok not a problem . So I wouldn't rely on that . I've not finished bal tech will get a call from Mr pain in the arse from salisbury

 

[Andy Allen]

Right if you look at next paragraph down that is what I challenged them on. Saying do not prime surfaces to be tiled on . I challenged them and they ok not a problem . So I wouldn't rely on that . I've not finished bal tech will get a call from Mr pain in the arse from salisbury

I know first hand priming certain surfaces using that adhesive reduces the bond strength considerably.

 

[Dumbo]

This is taken from there pdf, the adhesive is bal single part fast flex, an adhesive I use all the time on wooden substrates with cement boards...

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So just had a chat with bal tech and they say no need to from their point of view but you could to slow the porosity of the board but you should check with the manufacturer . The guy was very non committal and ambiguous but at no point did he say do not do it . I also asked if it would be detrimental to the bond strength and he said no . I dont know if bal board is a lightweight board , i know it not cementitous but they recomend priming with apd

 

[Andy Allen]

So just had a chat with bal tech and they say no need to from their point of view but you could to slow the porosity of the board but you should check with the manufacturer . The guy was very non committal and ambiguous but at no point did he say do not do it . I also asked if it would be detrimental to the bond strength and he said no . I dont know if bal board is a lightweight board , i know it not cementitous but they recomend priming with apd

Don't believe you...!

Do you have photographic evidence of you on the phone to them, holding a copy of today's news paper, along with a tape recording of the conversation....!...

Joking a part, if you had a failure on a job and primed the boards, I can guarantee, no, hang on , I can 25 year guarantee bal will blame that as it says in the pdf do NOT prime the board's...

 

[Dumbo]

Yes you are right . But to be honest if was to have a failure I wouldn't bother contacting anybody well not so since my dealings with bal when they told the grey colour grout i had was in their parameters for limestone . They are just dishonest the lot of them

 

[Bond]

If the hollow areas are small and isolated, you could cut-out / core the insulation and pour in some slc mixed with SBR, which should fill in any voids.