Floor plan - 135 sqm, 1.5 storeys, gable roof

If I were you, I would also have a completely new BP-compliant house designed and then have it adjusted to fit the existing financing.

Basically, you have to renegotiate completely. Your two-story building cannot be constructed. That would make the contract contestable and ultimately void for me. However, both parties are interested in cooperation. I would have a completely new offer drawn up for that instead of patching things up. Besides the lack of living space, with gable roofs the roofs are generally cheaper. For us, it was a 10K difference. Do you have that to spare?

That's exactly what I first communicated to the general contractor as well.

Yes, with the basic idea of "different house type, adjusted construction contract" I am totally with you – however, a wish that seems equally important to the OP in my perception is not having to reopen the financing again – that would have to be taken into account.

Changing the financing again is also somewhat complicated, unless you add refinancing at worse conditions. And I would like to avoid that at this point (or rather hope to avoid it completely). If the house would now become cheaper, I can surely think of something to still utilize the credit line...

If I were you, I would also have a completely new BP-compliant house planned and then have it adjusted so that it matches the already existing financing.

We have now passed on all questions and aspects to be clarified again to the general contractor. This includes the area, the house type (bungalow, etc.) and some other minor points which are irrelevant here. We will meet about this at the end of the week. Our requirement was to have the offer adapted and specified again according to the new situation. We shall see. (My concern is that the general contractor will refer to the argument that this is a "mixed calculation," which does not necessarily have to be that high. What then?) (I also received a new draft from the planner today... but I’ll leave that out here for now...)

(My fear is that the general contractor refers to the argument that this is just a "mixed calculation," which doesn't necessarily have to be that high. What then?)

That's bitter, but you need comparative offers from other general contractors. I wouldn't go along with it as long as I feel cheated. You can hint at that as well. If he acts weird when spoken to clearly, he's the wrong one for you anyway.

that this is precisely a "mixed calculation," which does not necessarily have to be that high. What then?) (I also received a new draft of the planner today...

How that high? - what sizes and prices does the new plan come to?

"So" how high? - what sizes and prices does the new plan come to?

I have already inquired more precisely by phone. The general contractor actually argues like this: It is a quantity/mix calculation, which is based on a fixed price per square meter of net floor area (around 1,600 euros) – completely independent of the house type. Only deviations from the services listed in the construction service description cost more. According to the general contractor, I could now simply build a bungalow with 135 sqm net floor area and that would be completely fine.

(By accident, I ended up on the rating function and rated the thread "bad" – sorry, it was not meant personally against everyone who is helping here I unfortunately cannot undo that)

In fact, the GU argues as follows: It is a quantity/mix calculation, based on a fixed price per square meter of net area (around 1,600 euros) - completely independent of the house type.

Those who build with bricks should not talk nonsense. For standard square meters, this is roughly true, but then he should move away from his carpet area thinking, because only one of the two calculation arguments can be correct at the same time.

I accidentally accessed the evaluation function and rated the thread as "bad"

I have been here for two years and don’t care about these little stars at all, precisely because in my opinion they are a sum of many unnoticed and many misclicked ones.