Drywall with brick construction method / Drywall properties

Drywall is perfectly fine. With insulation, the soundproofing should even be better than with bricks. But if you want bricks, just say so. It's your house.

It not only should be, it is so depending on the design. Interesting product from Knauf in this context: Silentboard - there are also various wall constructions in the datasheet with dB values (also compared to the masonry wall).

Hello everyone,
Thank you very much for the many responses.
That alleviates my concerns a bit.
I found hardly any information on the topic of drywall. And I don't know how reliable the sound insulation specifications of the Knauf walls really are. Does anyone happen to know where to get more information regarding the sound insulation values? From my research, it seemed as if all studies on the sound insulation of these walls were commissioned by companies like Knauf, etc.
Unfortunately, the architect planned so that our entire attic has to consist of drywall walls.
Solid walls would not be supported by the ceiling for structural reasons. That means we can only build with drywall walls.

Forget all data sheets: they can only calculate the product properties as such – but these are not "absolute," rather they shift considerably depending on the processing. Especially sound bridges are often small workmanship flaws or planning errors with big impact, which far exceed the "decibel" value differences between building material X and Y.

There are several reasons for lightweight walls. A main reason is labor costs for walls that have to be adapted to sloping roofs: in the past (with less insulation in the roof structure) one built "stepped" masonry, today walls have to be cut in a straight (slanting) line. This is more complicated with "solid construction materials" than with cladding of stud walls. In "lightweight construction" this can be done by considerably cheaper helpers. Another (weighty) important reason is that for non-overlapping walls it is advantageous if the "upper" walls are light. These two reasons concern houses with classic sloping "attics."

But even in the straight-walled "upper floors" of "city villas" one often uses "truss rafters," which in contrast to the common rafters span freely without "load-bearing walls" (as long as one does not want to make the top floor ceiling out of concrete).

Some walls are needed for the statics, not all architects are aware of that.

That one about statics was good^^

Yes, indeed: there are actually more and more architects who only think about load-bearing of weight and neglect the bracing effect against wind load.

Drywall construction in the attic is a good thing. Don't worry too much. The only important thing is that the walls do not stand on the screed and also that they interrupt the ceilings. Then everything will be fine.

Drywall in the attic is a good thing. Don't worry too much.

Exactly, it is only cheaper on the labor cost level, without being inferior; however, one should not generally do everything in drywall in the attic, somewhere the building must be adequately stiff relative to the breeze. But this has apparently been considered here:

The architect only planned two short interior walls in brick.

Do not build the drywall partitions from gypsum board, but with clay panels. Then you will have excellent moisture regulation and a very pleasant indoor climate - do not seal with "plastic paint"!