Raise the living room floor level

What does "klauen" mean? I have attached a snippet. Because of the insulation of the basement ceiling at the terrace, it is higher than the living area on the ground floor. And this height difference is supposed to be evened out by screed...

What is supposed to remain as clear room height on the ground floor after this elevation of the floor?

Who plans such shit without considering heights? All of that could have been planned differently and properly. Or is that no longer possible?

Solution: Reduce insulation by using different materials and a combination of internal and external insulation.

Reminds me a bit of the "Räuber-Bau". But you didn't notice it on the plan, only once the shell construction was up.

Thanks first of all for the numerous replies

What is supposed to remain as clear room height on the ground floor after this floor level increase?

Height is planned at 2.6m in the EB.

Who plans such crap without thinking about heights? It could all have been planned differently and correctly. Or is that no longer possible now?

Solution: Reduce insulation by using other materials and a combination of interior and exterior insulation.

So the building application is approved. Unfortunately, the architect did not point out the height difference to us, our general contractor only recently mentioned that the screed will be more expensive because of it.
Energy consultant (KfW55) planned 20cm polystyrene PS, slope insulation, and ventilated air layer with 2cm for the insulation under the terrace. Which insulation would be just as good but thinner? What do you mean by a combination of interior and exterior insulation?

Energy consultant (KfW55) has 20cm polystyrene PS, sloped insulation

PUR insulation WLG 22 or similar is better.

What do you mean by a mixture of interior and exterior insulation?

Insulation on the terrace and inside below the ceiling (e.g. PUR or foil-faced resol). I insulate my 60s old building, for example, only with 12cm resol on the outside to easily meet KFW 55 requirements.