Heat law => Solar system also in KFW85 house?

Hello here in the forum, we want to build a Kfw85 this year at the company Fjorborg, the house is supposed to be equipped with a gas heating system. Our Fjorborg consultant said that new buildings from 2010 onwards must generate part of their energy from renewable sources, e.g. through a solar system or a geothermal heat pump. However, I have read in the "Erneuerbare Energien Wärmegesetz" that if a house is 15% below the requirements of the Energy Saving Ordinance (after all, a KFW85 house meets this), this requirement is waived. Can someone tell me who is wrong now. Many thanks!

Hello,

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However, I read in the "Erneuerbare Energien Wärmegesetz" that if a house is 15% below the requirements of the Energy Saving Ordinance (after all, a KFW85 house meets this), this requirement is waived.

This concerns the Energy Saving Ordinance requirement regarding the use of renewable energies. The Kfw has its own requirements!
To what extent both are actually economical for the builder is a completely different question.
Regards

Hello,

then energetically the solar system could already be included.
I would therefore check whether the "regenerative energies" are not just a pretext.
You would then at least have a different negotiating position.

Regards