Install a new wall in an old building room

I potentially want to buy an old building apartment. It has a very large room (31m²). I am considering dividing it into 2 rooms by installing a wall.

Now I would like to get a feel for what needs to be fundamentally considered. Of course, I will also have a consultation with a professional. But to get a first impression of how sensible this is, etc., I am turning to you.

So, my questions would be:
- What needs to be particularly considered when installing a wall afterwards in an old building apartment?
- How about sound insulation? Is it possible to insulate the sound very well between the two rooms so that not every little noise passes from one room to the other?

Looking forward to feedback.

Thanks

The easiest way would surely be to install a drywall partition (metal or wooden stud frame clad with gypsum fiber boards and insulation in between). Then you will most likely not have any problems with the load-bearing capacity of the floor you are building on. The wall can possibly even be built cost-effectively by yourself or later relatively easily dismantled again. For sound insulation, you should make sure to equip the profiles at the floor and walls with separating strips for decoupling. Additionally, pay attention to the soundproofing properties when choosing the insulation material and possibly clad the stud frame with double layers (i.e. 2 layers of gypsum fiber boards on top of each other) on both sides or at least on one side.

The most important thing is not to extend the wall all the way up to the ceiling. There must be a gap so that no loads are transferred to a non-load-bearing wall afterwards. I like the note about the gypsumfiber (not cardboard) boards. We also did everything with gypsum fiber (and timber framing), because I don’t want papier-mâché in a wooden house. The old GK boards here also soaked up the plaster water nicely, and when you tear off the wallpaper, you immediately have the GK board in your hand. The worst junk, in my opinion, apart from the fire behavior. You can also take OSB as the first layer and then gypsum fiber on top. Then you also have more points where the gypsum fiber screws can go in.