ᐅ Insulation between aerated concrete wall and roof rafters? Minimizing sound transmission?

Hello dear forum community,

The week after next, the connections/seals on the upper floor between the calcium silicate walls and roof rafters will be installed. As a layperson, some of the openings seem quite large to me, in some cases 3-4 cm (about 1-1.5 inches) (see pictures).

Question: From your point of view, what is the ideal insulation material for these gaps to minimize sound transmission between rooms? There will still be joint compound applied, corner profiles installed, and finally drywall – but what should go in between?

Looking forward to your suggestions! Thank you.

I think insulation wool works quite well there.

Joedreck schrieb:

I think loose-fill insulation works quite well here.

Thanks, Joedreck.

Maybe this topic isn’t really problematic, and despite the seemingly quite large gaps, standard insulation material is simply used—and that’s that.

Perhaps some of you have experience along the lines of: “everything’s fine, no issues, even with the gaps and standard installation there’s no soundproofing problem between rooms.” That would also help me.

Have a great Sunday, everyone!