Electrical installation in the attic?

Yes, exactly, it is about the upper floor. My architect called it the attic. What do you mean by "If OSB boards are not yet installed, pull a cable in the small ring in place"? I think I will run everything under the screed. But how do I lay the cables for the lamps? Through the vapor barrier and drywall?

I did attach a photo after all. There are no boards on the wall yet. So first place a ring on site.

No, between the battens and OSB boards. It did not have to go through the foil.

You glued the cables directly onto the vapor barrier? But then the drywall sheets will go on top, wouldn’t they not sit flush because the cables are in the way everywhere?

The cables for the lamps are of course routed up to the attic and then come down.

Did you stick the cables directly onto the vapor barrier? But then the drywall sheets will be put on top, wouldn't they not sit flush because the cables are in the way everywhere?

Yes, exactly. No, there is still a battens layer in between. So from inside to outside: sheets-battens-foil. The sheets will be screwed onto the battens later. The battens are about 3-4 cm thick and provide enough space for the cables.