KfW 55 or 40+ for new single-family house construction in Würzburg?

[...] Regarding the ventilation system, there are probably 10,000 different opinions. If KfW 40 plus, then it is clear to us that one will be installed.

I don't believe that. In my initial research back then, I found significantly more voices in favor of a controlled residential ventilation system for KfW55. Even two friends in the field clearly advocated for it. My home builder no longer builds without it, so the question eventually didn’t arise anymore. Looking forward to good air in the house, especially during hay fever season.

KfW40 was a very simple calculation. Additional costs for house/roof were, I believe, 10K + photovoltaic + storage - subsidy - saved energy costs. That did not convince me, especially since the saved energy costs did not stand in a good ratio to the effort.

KfW40 was a very simple calculation. Additional costs for house/roof were, I think, 10K + photovoltaics + storage - subsidies - saved energy costs.

Well, 10k would fit with the current KFW 153 conditions. You basically get a better insulated house at no net cost. You only pay with the lost space due to the thicker walls.

Just for your information; for us it will be KfW 55, mainly because we do not want [WDVS]. Without that, it actually wouldn’t work in our case. However, I consider a controlled residential ventilation system a must, even at 55, but especially at KfW 40!

for us it will be KfW 55, mainly because we don't want an ETICS. Without that, it actually wouldn't work in our case.

Thank you for the feedback. Currently, we are also leaning towards that - possibly with 2 residential units, as our floor plan allows. But we also have an appointment with the energy consultant next week - let's see what they say. P.S.: We are also building near Würzburg

Even though the topic was already quite old and I was looking for a completely different topic, I got stuck here. But I have to admit that I only skimmed through everything.

Right at the beginning, one thing caught my attention:

That leads me to the following consideration:
Pro 40+:
- €12,000 repayment grant from the state additionally
- Lower heating costs, higher resale value
- Higher degree of self-sufficiency through the storage

As far as I know, the repayment grant is currently significantly higher for a KFW 40 Plus house and amounts to €30,000.
Please correct me if this is no longer true.

Since I am planning with KFW40 Plus myself, I had the idea:
Keep the battery storage as small as possible and the roof as full as possible.
To still take advantage of the KFW bonus.

In my case, there is also a subsidy from the federal state if I install a battery storage.

It was also already mentioned that for a new building, the air/heat pump + ventilation + etc., costs of up to 35% can be reimbursed by BAFA.

And why was I here now? Actually, I was looking for an overview of the electricity consumption of a house with an air/heat pump & household appliances per month/year.

I wish you a nice weekend!

And why was I here now?

....probably to build a maximum-subsidy house, if I understand that correctly All these parameters, insulation standards, etc. have an impact on finances and can play a role. However, many of the relevant measures also have an immense influence on the well-being in one’s own home at the same time. An insulation standard from a funding bank says nothing about that, even though that’s precisely why you build a house. From the private sector, I’m told that often things are funded that wouldn’t work on their own, and things that make sense or would work on their own are often not funded exactly for that reason... because they can function on their own. Therefore, I repeatedly suggest considering shifting the focus somewhat away from these prescribed KfW funding standards and not letting oneself be too whipped by them, which unfortunately often happens, as can be partially read here. First, it’s supposed to be MY house and a nice house in which I feel individually comfortable; funding aside. Living in a real passive house, for example, is a different experience, and I wouldn’t let a subsidy dictate the heating method etc.... I know a few examples...