Experiences with brine heat pump

I understood it that way too. But that would mean that many people, including here in the forum, do not plan their underfloor heating optimally?

Yes, that would be optimal. However, (wurde Ja auch schon angesprochen) there is no significant difference possible in the rooms of highly insulated houses today. The living behavior of our parents no longer exists!

Then the provocative question: Do modern, highly insulated houses, provided with [Kontrollierte-Wohnraumlüftung], even still need underfloor heating in the bedrooms if the occupants prefer it cooler there?

Planning includes planning services that cost money. Few companies inform a client about this (because it costs money).

This is usually a complete failure of planning.

Heat load calculation according to DIN
Hydraulic plan / pipe sizing of underfloor heating with installation spacing
Ventilation concept
....

With the heat load calculation, you know how much power the heating system must provide at a minus temperature x in winter. At the same time, you specify the room temperatures room by room.

Then it goes to the underfloor heating with the specification of the lowest possible supply temperature and the desired room temperatures or required heat to achieve the room temperature.
There the installation spacing in each room is determined.
It usually turns out that the underfloor heating in the bathroom is not sufficient. A wall heating might be needed...

The interest of a client to demand this is low with many companies, since this could reveal possible usual execution errors. (Heat pump capacity far too high, incorrect installation spacing of underfloor heating, too small piping of the ventilation system...)

Ich habe das auch so verstanden. Das würde aber bedeuten, dass viele Leute, auch hier im Forum, ihre Fußbodenheizung nicht optimal planen?

Then a provocative question: Do modern, highly insulated houses, provided they have controlled residential ventilation, even still need underfloor heating in the bedrooms if the residents prefer it to be rather cool there?

Interesting question. Our underfloor heating in the bedroom has not been in operation for 6 years (KfW70, gas).

So here’s a provocative question: Do modern, highly insulated houses, provided they have controlled residential ventilation, even still need underfloor heating in the bedrooms if the inhabitants prefer it cooler there?

Maybe no architect/civil engineer would want to plan it that way, as there are probably regulations regarding the furnishing of “living spaces.” As you can easily tell from the subjunctive, I’m an amateur. However, I can report that we have planned a small bay window adjoining the kitchen without underfloor heating. The door to the kitchen is kept closed because, in winter, the room could well serve as a refrigerator substitute. However, the ratio of exterior wall to floor area is disproportionately high compared to the other rooms.