The vapour barrier goes in the trash.

You don't want to use a vapour barrier at all if you will hang drywall. The moisture will move through the drywall but not the plastic and now you have mold conditions.

Keep the vapour in or out or allow it to pass all the way through.

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>Incorrect use of vapor barriers is leading to an increase in moisture related problems. Vapor barriers were originally intended to prevent assemblies from getting wet. However, they often prevent assemblies from drying. Vapor barriers installed on the interior of assemblies prevent assemblies from drying inward. This can be a problem in any air-conditioned enclosure. This can be a problem in any below grade space. This can be a problem when there is also a vapor barrier on the exterior. This can be a problem where brick is installed over building paper and vapor permeable sheathing.

https://buildingscience.com/documents/digests/bsd-106-understanding-vapor-barriers

If you _have_ to use it for code use certain tweed's which allows the interior to dry.

https://www.certainteed.com/insulation/vapor-barriers/

or shellac based primer on the drywall - in general.... it acts as a vapour barrier.

but I wouldn't use it in a basement without a LOT of ventilation.

I'm sorry but you are incorrect.

https://buildingadvisor.com/materials/foundations-sitework/basement-insulation/

I did that, but I used rockwool which is moisture resistant.

if you want to drywall the basement you want to remove those batts and replace them with unfaced batts, rockwool or XPS. Rockwool is moisture resistant.

and that includes paper backed insulation.

You do not want a vapor barrier on the inside of your. basement walls. The paper backing on the insulation is a vapor barrier. You should replace that insulation OR don't drywall over it.

https://buildingadvisor.com/materials/foundations-sitework/basement-insulation/