Strange. KfW told me that 40 plus works, only EE and NH do not. The costs must of course not overlap.
Yes, KfW told me that back then as well. However, in my opinion, that contradicts itself.
For 40Plus, you need a heat pump system, which is also subsidized by BAfA. Ergo: Not allowed double funding.
Therefore, old BAfA can only be combined with 40 or 55; optionally with NH.
But the NH package is very difficult to achieve for a single-family house. So far, there are only a few single-family house manufacturers that have a series certification for the NH package.
Considering the current development of construction costs, it is currently most lucrative for us to build KfW55 and take advantage of the old BAfA subsidy.