Raise the living room floor level

The question is justified. However, the screed alone cannot account for the high amount. And why an area of 220m²? Yet even with 220m² of cement screed CT25-F4-S45, this should only amount to between 7,000 and 8,000 euros.

The area of 220m² results from the basement and ground floor (both living and usable space and without garage). The offer states calcium sulfate screed 60mm in the entire basement and ground floor according to the energy consultant’s specifications. In the calculations from the energy consultant, there is also 6cm of poured insulation in the basement floor and 13cm of poured insulation on the upper floor. Could the poured insulation possibly be listed under the screed, or does that actually make no sense? How much does the poured insulation cost approximately? (Basement 105m²; Ground floor 115m²) Otherwise, the costs are probably really that high because several layers of screed are planned on the ground floor; which is actually not stated in the construction service description. Hopefully, the reduced insulation thickness on the terrace works out, especially in the current times...