KfW Supplementary Loan 358 for House with Granny Flat

Hello everyone,

I have a question about funding through the KfW supplementary loan (Program 358), maybe someone here already has experience:

I have already been granted a subsidy for my roof project, and the construction has already been carried out. Now I want to use the supplementary loan through Program 358 because the conditions there are significantly better than with 359.

In the application it was stated that the house has a granny flat – that was the original condition. In fact, we are using the house entirely ourselves as a single residential unit. There is no separate rental, no second household, etc.

My questions:

[*]Is Program 358 still possible if you can prove that the house is in fact only one residential unit with owner-occupation?
[*]Should one possibly change the residential unit specification afterwards, even though the funding notice has already been issued?
[*]Or can the loan simply be applied for only for the self-used unit, although formally two residential units were stated?

The bank and KfW say the loan can basically be applied for – but of course I want to make sure it really falls under 358 and doesn't later end up in the wrong funding category (359).

I am grateful for any experience or assessment!

At the time, the application stated that the house had a granny flat – that was the original condition. In fact, however, we use the house entirely ourselves as a single residential unit. There is no separate rental, no second household, etc.

In which application was that stated?

Hello, in the original BAFA application BEG EM, that is individual measure. In combination with this, I could then also receive the supplementary loan. I have already received the BAFA grant notification in 2024.