Site planning and floor plan - Your assessment wanted

Yes, of course you have to accommodate the roof pitch accordingly. But you are prioritizing the attic, not the living floor. Think about it: I would prefer a comfortable floor rather than a comfortable storage room. Boxes can also be stored in an attic that is only 1.50 meters high.

As I said, we addressed exactly that with the construction company and he understood the problem / our request of course. He would implement it if it weren't for the building regulations issues. I can't really explain it well here, but it was a mixture of the floor volume, the angles, etc. We also double-checked with the municipality. The contractor knows our village very well, as a lot of construction is currently being done with him.

I always plan these walls simply with a thickness of 30cm

Lalala, thirty centimeters, no way, little Peter ...
How many decibels of rutting cry absorption are you aiming for with that?

I am always amused by the widespread trivial physics head cinema idea that you can scare sound away with a hair gel bouncer of the brand Ey man you ain't gettin' in here

Sound can play Mikado, it comes over the smallest bridge

but it was a mixture of the volume of the floor, the angles etc.

So, in short, the full storey trap.

Lalala, thirty centimeters, no way, little Peter ... How many decibels of rutting scream absorption are you aiming for with that?

I am orienting myself on the regulation for the wall thickness that should be between 2 apartments. I had read that somewhere once. Of course, it may have changed by now. But you can make a better suggestion. I already said that I am not an expert for the execution.

With that, I base myself on the regulation for the wall thickness that should be between 2 apartments. I once read that somewhere.

30 cm - in the Bäckerblume?
Usually, 24 cm in stone or 20 cm in concrete are mentioned there, but...

I already said that I am not an expert in execution.

... at least in one of our private messages, I probably have been once. Because that primarily falls under the field of fire protection, which is a broad area in itself, and as a general medical business consultant, I don’t even attempt to dabble in it.

In fire protection, it is about delimiting fire compartments, where, for example, gypsum offers more than "mass."

The semi-specialist press focuses more on the basic idea of having load-bearing walls as supports for ceiling panels. In multi-story residential construction, this is the more significant aspect of soundproofing: that for the enclosing walls/floors/ceilings, the principle "everyone has their own" is given great importance. The trick with sound bridges is that they can be effective even if small. But that is also a field in itself and I am rather a non-swimmer in it. For me, it’s enough just to be able to smile about “more is more.”

30 cm - in the Bäckerblume?
Usually, 24 cm in stone or 20 cm in concrete are mentioned, but ...

24 cm + 3 cm of plaster on each side. That's how I read it too. It's about 30 cm, Mr. Bäckerblume.

To what extent the floors are or need to be decoupled from each other, I have no clue either. But maybe the OP will ask their planner and then tell us.

To what extent the floors are decoupled from each other or need to be,

Legally, it probably doesn't "have to" be in a single-family house. Normal floating screed – on which the partition wall does not rest – should be sufficient.

24cm + 3cm of plaster on the left and right.

Manometer, 3 cm of plaster would probably already need reinforcement so that it wouldn't come off from marital passion. By the way, baker's yeast infection was only suspected, I prefer the Apothekenumschau ("Back" like Horst, white notice) *smile*