2016 KfW Efficiency House 55 according to reference values (U-values)

That would be new and is at least according to the KFW leaflet for the KfW55 house not yet known. It only states that the current conditions apply at the time of conclusion.

Right now, you get a repayment subsidy of 5% for KfW55, a doubling to 10% when reaching KfW40, and the subsidy is limited to EUR 2,500 or EUR 5,000.

The doubling of the loan amount for KfW55 from EUR 50,000 to 100,000 is NOT a subsidy.

Please explain your % figures and the source.

It is very likely that from 1.4.16 there will no longer be a repayment grant for KfW55, for which purpose KfW40+ is being created...

oleda... where did you get this info from?
my info from a phone call with KfW is that it stays like this with the 5%

According to the overview for the "153iger" on the KfW homepage, the subsidy for KfW70 is being discontinued, but according to the KfW homepage, the subsidy for the KfW40 plus house is additionally being introduced with an "attractive repayment grant". Therefore, the assumption is that the repayment grant for KfW55 will be eliminated.

If I understand correctly, with the "KFW Efficiency House 55 according to reference values" the KFW verification process is significantly simplified. You only need to demonstrate the prescribed insulation values for exterior walls, roof, windows, as well as an appropriate heating system. I hope I understood this correctly? Who has to certify this proof, is the architect sufficient or does it have to be an energy consultant?

What happens if, for example, the windows exceed the values, can this be compensated by better insulated exterior walls, or do you quickly end up back at the more complex calculation?