Heating planning - selection, but how? Questions upon questions...

Hello everyone, the topic of heating is slowly driving me crazy, for me one of the most difficult points in house construction overall. Depending on whom you ask or which study you find, there are sometimes quite different facts and opinions...

Regarding my facts: We are planning a KfW70 with underfloor heating through a general contractor [GU]. The [GU] has mostly installed gas boilers in the past, which, however, must be completely ruled out for us. My assessment is that the [GU] therefore has a lot of experience with gas but less with heat pumps. Now he has presented us with a proposal including a heat pump and solar thermal system, although I am quite skeptical about the economic efficiency.

I would therefore like to have a (hopefully) independent opinion or economic efficiency calculation. How would you approach this topic? How did you have your heating system planned ([GU], heating specialist company, specialist planner/planning office)??? What would an assignment with the specialist planner approximately cost?

ST with heat pump is not sensible - generally no buffer tanks for heating with heat pumps. If anything, photovoltaic. Furthermore - we are painfully realizing this right now - find a heating engineer who regularly installs heat pumps (preferably nothing else)... with all others you risk them having no idea about it. I believe if you find one who is really good, you don't need a specialist planner or a planning office... Pay attention to details and question the execution - e.g. 6 cm cement screed is not enough for 20 mm pipes. Consider wall surface heating in the bathrooms (no towel radiator). Check the plausibility of the heating load calculations you receive.

Hello everyone, the topic of heating is slowly driving me crazy, for me one of the most difficult points in house construction at all. Depending on whom you ask or which study you find, sometimes quite different facts and opinions...

Regarding my facts: We are planning a KfW70 with underfloor heating through a general contractor (GU). The GU has mostly installed gas boilers in the past, which completely must be excluded in our case. My assessment is that the GU has a lot of experience with gas but less with heat pumps. Now he has made us a proposal with a heat pump and solar thermal system, but I am quite skeptical about the economic efficiency.

Therefore, I would like to have a (hopefully) independent opinion or economic efficiency calculation. How would you approach this topic? How did you have your heating system planned (GU, heating specialist company, specialist planner/planning office)? What would roughly be the cost of commissioning a specialist planner?

Why no gas? Is there a ventilation system? The GU will probably look for an inexpensive heating installer to install the heat pump for you. Whether it will run error-free afterward could – as Baheija wrote – be a gamble.

No gas line in the street and it also does not meet KfW70 standards, according to the certified KfW planner of the house. Options included even better windows although it is already triple glazing and partial cost coverage for gas line in the street (gas provider)

no towel radiator

No good experiences? Was thinking of a combination of underfloor heating + electric.

Electric heating costs 1 kWh of electricity for every kWh of heat... Electricity is expensive - better to increase the heating surface in the bathroom and thus cover the demand - or just say goodbye to 24°.