Kfw70 with poroton and utility water WP + gas + decentralized ventilation

It is similar with us as well. In terms of insulation (Ht) we are between KFW40 and Kfw55 requirements. Due to lack of solar support and only using gas condensing boilers and controlled residential ventilation with heat recovery, in the end, barely a KFW70 is achieved with great difficulty. I also prefer to invest more in insulation than in technology. However, there are limits to what makes sense here as well... As small gas condensing boilers in this area, Thision is often mentioned. They have a device that can modulate down to 1KW.

Hello everyone,
Thank you very much for the numerous comments, the calculation of heat demand etc. is according to the architect not yet completed...
I will inform you about the situation as soon as concrete updates are available.

Thanks again!