Build partition wall

[Gladh]

I have a carpenter (from Poland) who claims that it's a good idea to put plastic under the gypsum on both sides of the partition wall

It's a downright bad idea, because any moisture that gets in there has no way out. Replace it with some diffusion-open paper instead, if you're afraid the insulation will creep out through 2 boards, which to me seems completely impossible.

 

[Mats]

Skip that plastic.

Gypsum, stud, gypsum is excellent as an interior wall. If you want to go luxury, use gypsum, OSB, stud, OSB, gypsum.

 

[ohlgren]

I skipped the plastic. Feels unnecessary and a bit risky.