Insulate new construction 36.5 aerated concrete?

36 aerated concrete with gas and 8m2 solar thermal is enough for kfw70.

Neighbor built like that!

Good morning,

Thank you for the quick responses.

Regarding the air source heat pump, the energy consultant said that nowadays these can operate without electricity down to -10°C. Only then does an electric heating element have to "warm" the ambient air - this effect can be further reduced by installing photovoltaic panels on the roof (payback period approx. 12 years - cost approx. 1400€ per kWh). He was not in favor of solar thermal and said it is better to stay away from it.

Also just another half-truth!

Air-to-water heat pump with solar thermal is nonsense!

Our air-to-water heat pump had 0 operating hours at 23 degrees room temperature "kfw70" during the low temperatures in January.

Photovoltaics without storage is also just another half measure and the costs probably never really pay off.

People. I am not a technician, not an engineer. I am not in love with technology either. It just has to work. And both the builder and the heating engineer advised us to go with the combo Solar thermal/Gas heating/Ytong. Because it is the most cost-effective in both acquisition and operating costs. Of course, this air-water heat pump heats without gas, with air and electricity. It is a pump, an inverted refrigerator. The energy savings effect, I was told, is hardly achieved due to the additional costs of the system, one or two harsh, really harsh winters completely ruin the balance. And they are supposed to be more prone to repairs as well. Solar is cheap and proven. And we have a south-facing roof without any trees in front of it. The Ytong also works. Used millions of times, sound insulation somewhat worse, so what, we live in a rural area. But no Styrofoam on the wall. And in one week the masonry crew finishes the shell. The stone saves labor costs. You can tell that in the house price. Oh, and later you can easily hammer a nail into the wall. Also pretty nice.

On the topic of air heat pumps, the energy consultant said that nowadays they can operate without electricity down to -10°C. Only then does an electric heating element need to "warm" the outside air.

Pass me the popcorn .... where did you find this "energy consultant"? Send him to the desert!

The heating element is there to defrost the fan in the outdoor unit; don't send him to the desert, send him to training instead!

The energy saving effect, I was told, is hardly recouped by the additional costs of the system, one or two severe, truly severe winters completely destroy the balance.

"One" has to stand in for everything as well. It seems to me as if all the simple minds have gathered here.