Energy Saving Ordinance Standard or KfW55 (without KfW)

See description. I think with our requirements we are probably already almost at KfW55 anyway?

The description is a bit thin and regarding the KfW categories I would simply discard them and think in terms of measures or properties. So which wall construction is desired? If ETICS is desired anyway, it can be done "properly". Also, how should the attic be? If it is inhabited, I would insulate properly there as well to avoid it getting too hot in summer.

Our prefabricated house manufacturer did not have KfW55 as a standard and pointed out to us at one or the other point that since we are not building according to KfW55, we would save a few thousand euros here and there.

You also don’t have one, if I remember correctly, that I would have recommended.

The description is a bit thin and I would simply disregard the KfW categories and think in terms of measures or characteristics. So what wall construction is desired? If an ETICS is desired anyway, it can also be done "properly." Also, how should the attic be? If it is inhabited, I would also insulate properly there so that it does not get too hot in the summer.

Honestly, I haven't given much thought to the wall construction yet, since until today we actually wanted to build KfW40+ and this would thus be predetermined. The attic will be inhabited. Whether it is KfW55 or not actually doesn't matter to me in the end. The requirements from the description should basically be met + the maximum cost-benefit ratio in other aspects, such as insulation and wall construction.

Cutting in the sense of shortening, letting the air out. Not in the sense of painting ;-) I mean providers of Effizienzhaus 55 caliber 36.5 monolithic, if I remember correctly.

Of course, I understand that shortening is meant. But how do you come up with exactly 20sqm when you don't even know the other framework conditions? :)

But how do you come up with exactly 20 sqm when you don't even know the other framework conditions?

Because a handful of developers, whose domain is this type of house, demonstrate functional models with around and under 145 sqm of living space and have been selling successfully for a long time. So you can find dozens of proven house designs that manage with less space to this extent than you aim for.

Honestly, I haven't really thought about the wall construction yet, since until today we actually wanted to build KfW40+, and that would therefore be predetermined.

If KfW55, then a 36.5 cm wall is sufficient. Then no additional ETICS is needed.