House construction, KfW Efficiency House 55

So then, hopefully understood correctly.
Stein Poroton is good, but only 17.5 cm is too little. The 15 cm external insulation Styrofoam is not ideal even if it achieves the thermal value.
Would the Poroton t9 36.5 cm filled with perlite be sufficient?? What additional costs should I expect?
Then if geothermal energy is not possible or too expensive, a reasonable gas heating system.
For ventilation, preferably no central system but only install ventilation as needed in the wet rooms?
Triple-glazed windows should probably also be included.
Can I achieve a KFW 55 house with this?
Best regards, Xinette

Not? Well then, explain what the AZ is...

Hello,

What does that mean? Assuming your house has a heating demand of ~20,000 kWh in the end, you would consume 7,100 kWh of electricity here

In a new building ... ?

If it’s about the ideal, brine-water heat pumps would probably be preferable - they cost significantly more, but have COPs of about 5.

The current maximum would be a groundwater or water-water heat pump

Rhenish regards