Freestanding bathroom wall: Does the wall hold a double washbasin?

That would certainly be the best! But somehow that doesn’t quite fit. I think I will screw such a floor profile to the floor and embed it in the masonry. Does anyone possibly know an alternative to the Würth profiles?

There are plenty of solutions. You could simply screw 2-x stronger L-profiles into the floor in front of the screed, they are fixed with heavy-duty anchors. What is the ceiling made of? Concrete with steel or wood? There are also professional solutions like the GIS system from Geberit, but I guess that won't be cheap.

What is the ceiling made of? Concrete with steel or wood?

I interpret the desired structure as cantilevered upwards.

I interpret the desired structure as freestanding upwards.

I think it is about the "ceiling" under the bathroom.

We want to build a freestanding wall in our bathroom (approx. 2m x 2.2m). I

... 11ant thinks that the wall should not have any contact with the ceiling, but simply end after about 2m or 2.2m. And this should be taken into account in the execution, especially since washbasins are to be hung on the wall.

Correct! Ceiling connection is not simply possible in this area. The whole thing is located in the attic, and the rooms are open up to the ridge (approx. 4.5m to the ridge beam).