Build less than requested and approved in the building permit

Good morning everyone!

Things are progressing. We are currently planning our little house and want or rather have to (due to the fixed price guarantee from the house installer) submit a building application within the next 10 months. However, construction will only start at the end of 2023/beginning of 2024, as the installer's order books are full. The civil engineering, and thus the biggest risk in our cost calculation, will therefore only take place next year, well after the building permit.

If the civil engineering costs significantly more than planned, we would specifically forego an expensive bay window extension including a balcony. If the costs remain within budget, we will stick to the planned bay window.

Now my question: In the building permit, we have to apply for and get this bay window approved (which is unproblematic so far, everything is within the building window, the floor area ratio is complied with, all okay). However, if we have to forego it for cost reasons, we would no longer comply with the building permit, but would build "less" than was approved. Has anyone had experience with this? Can I just do this "as is," or do I even need a completely new permit?

Thanks in advance for your assessments!

You can have the approval adjusted afterwards. Search for "Tektur"

If I have googled correctly, the Tektur is submitted before the building permit is utilized. If the civil engineering work starts, the construction has begun and thus the permit is in effect, right?

We are currently planning our little house and want or have to (because of the fixed price guarantee from the house installer) submit a building application within the next 10 months. [...] If the civil engineering costs significantly more than planned, we would concretely do without an expensive bay window extension including balcony.

Ten months are absolutely more than enough for the forum community to discuss your (non)bay window more extensively than it would be built :)