Double drywall on plywood, do all the joints need to be over a stud?

[Henrik.S]

I am thinking of soundproofing some interior walls and therefore using double drywall on plywood. The wall is cc60, and I only have 90-drywall. Is it okay if some drywall seams end up in the middle between the studs and are only screwed into the plywood?

The screw gets a good grip in the plywood, and the wall should become stable enough that vibrations won't cause the seams to flex, right?

 

[Hojte]

Yes, exactly, as long as you don't splice over a place where you've spliced plywood, it should be fine.

 

[prototypen]

If you screw the plywood properly, it works. Stagger the drywall joints for even more strength. I wouldn't screw the first layer of drywall too much.

Protte

 

[-RB-]

In practice, it will work to let the drywall joints land between the studs if the plywood and drywall are not joined in the same place. But in theory, all layers should be screwed into the studs. See for example this thread https://www.byggahus.se/forum/threads/hur-faester-man-gipsskiva-pa-osb.374712/.
In short, it depends on what the sheet manufacturer prescribes. If you want to do the job "by the book", that is.

 

[Henrik.S]

Good thread, didn't find it when I searched before. Shared opinions then (as usual here ). But I'll probably embellish where it fits simply.