Plastic under Eps-cement

[Baskavoda]

I am going to cast an intermediate floor with ePS cement according to gvk's description

https://www.gvk.se/branschregler/golv/forstarka-trabjalklag/lattfyllnadsmassa

Have tried to find the right type of plastic to use. The construction market mostly sells the usual age-resistant 0.2mm thick plastic that should not be used.

At byggmax they sell a thinner plastic

https://www.byggmax.se/verktyg/täckning-rep-och-ståltråd/golvtäckning/täckfolie-handy-p21011

It says that you are not allowed to build it in. Can anyone suggest what I should use? Or can I use the one from byggmax?

It is about ensuring that the concrete can dry out downward since I will have a waterproofing layer on top where the bathroom will be.

 

[nino]

Take the byggmax foil
The purpose of the plastic is to prevent the water in the EPS from being absorbed into the surrounding studs, etc., as it will dry out too quickly.
The reason it is stated that the foil should not be built-in is that it is not age-resistant and cannot be used as, for example, a vapor barrier in walls.

 

[Landbogården]

Borrowing this old thread as it has my current question.
Why can't age-resistant building plastic sheeting be used under EPS concrete?

The instructions from all EPS concrete manufacturers state that a PE plastic sheeting that is not age-resistant should be used, but no explanation as to why.

 

[Peter2400]

Borrowing this old thread as it has my current inquiry.
Why can't age-resistant building foil be used under EPS concrete?

The instructions from all EPS concrete manufacturers state that a PE foil must be used that is not age-resistant, but there is no explanation as to why.

I think they mean that it doesn't NEED to be age-resistant.
It really can't make any difference.

 

[nino]

Borrowing this old thread as it has my current question.
Why can't age-resistant construction foil be used under EPS concrete?

Instructions from all EPS concrete manufacturers state that a PE foil that is not age-resistant should be used, but there is no explanation as to why.

Against wooden structures? Or where do you mean?

 

[Baskavoda]

I think they mean it doesn't NEED to be age-resistant.
Can't make any difference whatsoever.

I also pondered this when I placed EPS in my subfloor under the bathroom. The difference is that the age-resistant one is completely sealed and doesn't let through any moisture. I'm thinking that the EPS needs to be able to dry out downwards (slowly) and that's the reason it shouldn't be completely sealed underneath.