Retro fit ufh & Hydrogen gas causes floor failure.

[Italy]

Yes I see them.
What are they?

I need to know you !!
I have never seen them before.
Do not you recognize them?
you are the tilers of the panels !!
I do not use panels

 

[Old Mod]

I need to know you !!
I have never seen them before.
Do not you recognize them?
you are the tilers of the panels !!
I do not use panels

No, I do not recognise them, I have seen board with similar colour.
I do not remember where

Anyone else recognise the motled green boards in the photo above?

 

[J Sid]

No, I do not recognise them, I have seen board with similar colour.
I do not remember where

Anyone else recognise the motled green boards in the photo above?

yes carpet underlay

 

[J Sid]

or quick step underlay

 

[Ajax123]

So using an anhydride screed over aluminium would result in the same reaction Alan yeah?

So would that translate in to any anhydride suitable products like Anhyfix adhesive, or Anhylevel have the same reaction? Just trying to clarify.




I know you know you're correct, but we can definitely confirm that, through our research we found that a lot of priming methods were ineffective.

Any further info would be helpful Alan, thanks.

Any alkali in contact with the un oxidised aluminium foil on insulation will have the same reaction. That goes for gypsum levellers, screeds and tile adhesives as well as those based on cement including sand cement sreeds. With gypsum the reaction is somewhat slower as tge evolution if hydroxyl ions is slower. Typically though it will still happen within a few hours of application. With gypsum screeds it results in what look very much like mole hills on the screed surface. I gave been able to limit it in the past by applying several thick coats of PVA. Yes I said PVA... lol. I have never found a suitably practical priming technique that was guaranteed to overcome it though. Interestingly if the foil has been around gircacejile and has oxidised the reaction us much less pronounced. I did try using a vinegar solution to promote oxidation once but the whole house stank for weeks after.

Epoxy might work but it would be an expensive solution.

The reaction is partly the reason why all floating screeds should be placed on a polythene slip membrane.

 

[Old Mod]

Thank you Alan.

I have never found a suitably practical priming technique that was guaranteed to overcome it though..

Are you able to guess as to why Mapei state that they're eco prime and grip works as a primer Alan?

 

[Dumbo]

Any alkali in contact with the un oxidised aluminium foil on insulation will have the same reaction. That goes for gypsum levellers, screeds and tile adhesives as well as those based on cement including sand cement sreeds. With gypsum the reaction is somewhat slower as tge evolution if hydroxyl ions is slower. Typically though it will still happen within a few hours of application. With gypsum screeds it results in what look very much like mole hills on the screed surface. I gave been able to limit it in the past by applying several thick coats of PVA. Yes I said PVA... lol. I have never found a suitably practical priming technique that was guaranteed to overcome it though. Interestingly if the foil has been around gircacejile and has oxidised the reaction us much less pronounced. I did try using a vinegar solution to promote oxidation once but the whole house stank for weeks after.

Epoxy might work but it would be an expensive solution.

The reaction is partly the reason why all floating screeds should be placed on a polythene slip membrane.

Is that why we put slip coats on celotex

 

[LM]

The calcium hydroxide aluminium reaction is fairly basic chemistry. The same thing happens when you put calcium sulphate direct to aluminium. Priming has generally proven to be ineffective in preventing the reaction so the best thing js to avoid it altogether by either not using aluminium or putting a slip membrane down first.

I hope you ran this past Spacey first Alan before posting

 

[hmtiling]

My epoxy primer shout wasn't that silly then

 

[J Sid]

Thank you Alan.



Are you able to guess as to why Mapei state that they're eco prime and grip works as a primer Alan?

there's very little that they claim that can't do.
use it to prime resin backed stone, painted epoxy floors, gypsum
its a wonder product