KfW70 with gas condensing boiler and solar is definitely not possible

and K1300S

Thank you for the tip. I will ask about it a bit more specifically again. I also can't really imagine that everyone paid a small fortune for it.

In short: Kfw 70 is achievable with little effort, for KFW 55 it requires disproportionately more. That’s why, in my view, you have to be quite green for it, while KfW 70 can rather be justified from a standpoint of reason. My opinion.

Hi

I have to admit I don’t know myself as well as I would like to yet, but today I received the KFW approval

Being built:

30 cm aerated concrete
Gas heating with solar for hot water
Ventilation system with heat recovery

2 full floors
150m2
Without basement

Hope it helps, otherwise sorry

If it helps, I can also take a look in the documents to see what my primary energy demand, etc., is

Regards

KFW 70 with 30cm aerated concrete?? I can hardly believe that, you will never be able to meet the requirements without external thermal insulation composite systems (ETICS). With a simple 30cm aerated concrete wall, you will at best achieve a U-value of 0.28.

However, I also don't understand why KFW should not be possible according to the specifications of the thread creator. Basically, solar energy is not even necessary. We want to build with controlled residential ventilation and a gas boiler and can therefore do without solar.