OSB between vapor barrier and moisture-resistant drywall + waterproofing?

[Archangel_1]

Live in a house

Can I place OSB directly against the vapor barrier and then install wet room gypsum board and thereafter an approved wet room barrier/foil?

Or am I exposing the OSB to a possible mold risk, since it is between two moisture barriers? (the vapor barrier and the wet room barrier)

Does anyone know?

Best regards / A. :blushing:

 

[Stefan N]

You should not have a diff if you have waterproofing.

 

[Oasis]

It is exactly as you say, you risk trapping moisture if you have both a moisture barrier and a waterproofing layer. So, you should remove the moisture barrier.

 

[Archangel_1]

Wait now...

The vapor barrier was there from the start when I took down the bathroom. Behind tiles and ala-standard gypsum -1999, the vapor barrier was there, so maybe it was wrong from the beginning? or no, but it's there so you don't get moisture from outside?

1:
Now possibly an OSB will go up, but then the vapor barrier should be in front of the OSB, meaning when the OSB is installed I put back the vapor barrier?

2:
If I skip the OSB and use wet room gypsum, should there be a vapor barrier behind the wet room gypsum?

Stefan: you mean that the vapor barrier should not be against the exterior wall if I'm making a bathroom? Regardless of whether it's framed with OSB or not before the wet room gypsum goes on?

/ Thanks for the answers / A.

 

[injonil]

You've already received answers to your questions.

 

[Stefan N]

Run OSB+Gips and no diff.