Elevation and floor structure. Was this done correctly?

Hello,
we are currently having the floor structure done. A total of 16cm is planned. These are divided as follows.
5cm Styrofoam
3cm mat for underfloor heating (for stapling)
6cm screed
2cm floor covering (tiles)
The 5cm and 3cm panels have already been laid. Next, the pipes need to be installed. When we were at the house today and measured from the height mark to the upper edge of the underfloor heating mat, we got values between 106cm and 107cm. That means to me that we are missing 1 to 2 cm. We do not believe that the height mark was applied incorrectly. It was applied already during masonry and again after plastering the walls. The markings were almost identical. The correct panel thicknesses were also used correctly (5 and 3cm). We don’t know if we are worrying unnecessarily or if something is really wrong. We also notice that when walking on the mat, it sinks a bit, meaning it can be slightly compressed.
Could it be that the mats are compressed further by the weight of the screed?

When the underfloor heating pipes disappear in the screed, I come to your mentioned 16cm by addition. Where do you see the problem? Is your cross-section underfloor heating pipes plus 6cm screed height or inclusive?

According to the height section, only 6 to 7 cm seem to be left, although we still need 8 cm for screed and tiles. The 6 cm consist of the diameter of the heating pipes and the 4.5 cm minimum covering of the pipes. The problem I see is that, for example, we might no longer be able to open the front door. Therefore, I wanted to know whether the already laid panels are compressed a bit more by the weight of the screed or if we already have a problem. When the height section was installed, we checked several spots. The line was 16 cm above the raw concrete ceiling, and now suddenly 1 to 2 cm are missing, although the planned thicknesses of the mats were installed.

I understand now. hm, I don't know that either, I didn't measure something like that back then. I would ask the site manager or the screed layers.

Unfortunately, you always only write generally about "boards". With thermal insulation boards, nothing will compress because the board structure is rigid and firm. For impact sound insulation boards, the usual amount of compression is at most about 2-3mm per layer (from a practical point of view). Regards: KlaRa