Floor insulation not glued/sealed to the screed

Nothing was glued there with us, but the entire underfloor heating was mounted differently. But underneath are only Styrofoam panels as well

Phew, those are really large gaps, someone has based the heating load calculation on the standards from 1980 again.

Why should the floor mold? The underfloor heating dries everything out. Mold has no chance there. The silverfish have a different origin.

Because the water runs from the screed under the insulation boards and cannot dry properly there even with dried screed. But I am an amateur. I have just read several times that exactly this can lead to big problems and that it is not so rare either.

But this only occurs if the liquid screed is not mixed properly and the water separates.

District heating, they have already complained that we require less energy than average.

The pipes were laid according to the calculation from the manufacturer. In the bathroom, the pipes are close to each other due to the higher room temperature.

I even believe you, but it is still suboptimal because, as I have already mentioned, you will unnecessarily heat with a higher supply temperature. This will also lead to higher heating costs than necessary.

But it doesn’t matter that you don’t understand what I mean. You will understand once you want to optimize your heating system and wonder why some run with a supply temperature of 25 degrees and yours from 30 degrees upwards.

But since that is how it is, you shouldn't be upset about it. What is, is.

I see no problem there. As stated, the whole thing was calculated and laid accordingly. And that by the manufacturer, not by the plumber.