Buy land with cash, construction through KfW/NRW Bank

You are forgetting the living space..

I understand, thanks, we'll skip the granny flat.

I think I just made a mistake in reasoning or rather . The floor area ratio means the maximum building area allowed on the base level, the second floor doesn’t count, right? If I fully use the 100 sqm, for example, then I could also have 100 sqm on the second floor?

Wouldn't a garage or the space in front of it reduce that even further?

Here is the answer:

exceeded: - In WA 1 (our area) up to a value of 0.5

. .

100 sqm would really be very little – walls etc. would reduce the actual area even more, right?

No, the floor area ratio refers to living space.

First lived in yourself,

Once again: A granny flat is a separate residential unit that is equipped so that one can live there independently of the main apartment. It is an apartment, but subordinate. Mostly because of its size. Nevertheless, it is separated by a secure lock on the apartment door from your main apartment!

with the option to later let parents live there.

How many sqm do you want the parents to live in? Or do you mean locking them away? Sorry, after #7 you should really read through the entire building code and additionally your building regulations. There are fundamental gaps. That’s not bad. However, building a house is too complex to wish to build a “Villa Kunterbunt” on a community plot. And no: the floor area ratio regulates the total living area, whereas the site coverage ratio regulates the buildable land area. Honestly, I’m waiting for you to correct your opening thread and improve by meaning site coverage ratio. That makes more sense with 256 sqm for a semi-detached house development. Floor area ratio would be quite small and would deter the target group because families won’t be found there. At least not at the plot price. However, I can also imagine that 2 residential units on a semi-detached house plot are not allowed. It is very likely that you are mixing things up out of ignorance. That is not bad either. What is bad or not good, though, is that you plan your thoughts on an imagined basis. And that does not lead to the goal. Anyway: Granny flat in a semi-detached house that you want to live in yourself on a 256 sqm plot is one of the worst ideas I have ever read. Focus on your needs and room program as well as the development plan, which we do not know.

You meant plot ratio.

I have now found that it is the plot ratio in the development plan. 2 apartments are allowed, as well as 2 floors (probably not possible otherwise). Accordingly, in theory up to 100 sqm per apartment would be possible. Sorry that I misunderstood that. It is correct that I am still a complete layman, but that is why I also reached out here to learn. Reading the technical legal jargon will hardly help me. I want to talk about this beforehand before entering into any obligations related to the property and then being surprised. I am happy to be corrected and do not want to contradict anyone here, I am just expressing my thoughts on this as a layman. By the way, unfortunately I cannot edit anything after 4 minutes.

The terminology is pretty stupid, in my opinion.

It is a determination. Seen that way: law. But.. all good, you are entitled to any question. You just have to look at the overall concept.
Just post the PBlan, complete, not only excerpts, and definitely the textual part. Only small puzzle pieces without the whole cannot be used to assess the developability.
Please no links, links are not allowed.

Just set the PBlan overall

Here is everything I have available in the attachment, had to make it into a picture because PDF is not allowed

What does the property belong to? I would say: WA 5.
Means 0.5 floor area ratio, terraced housing, one residential unit.