Exceeding the floor area ratio

The provisions of the Baunutzungsverordnung that were valid at the time of the publication of the B-Plan apply. In the various versions of the Baunutzungsverordnung, there are indeed different calculation methods for the floor area ratio/GFZ.

And: not everything visible in the built environment has a building regulation approval ...

What you are showing is only the legend. The plan drawing as well as the textual determination and the current use of your property apply.

No further notes on the floor area ratio are made in the plan. Attached is another image of the plan drawing. The number 0.4 is indicated for my area there.

And: not everything you see in the built environment has a building permit...

I am asking here and have also specifically spoken with the municipality to do everything according to the rules. The building regulations already indicate that the floor area ratio can be slightly exceeded and that this would not be such a big deal. Slightly, of course, is a matter of interpretation. I actually do not assume that everything in this street is approved. But that does not bother me and is none of my business. I would rather ask myself how likely it is that something like this could ever lead to problems. So how could something like this come to light? I live in the countryside.

According to my internet research, there are exceptions that can be credited or utilized. I saw there that garages and driveways sometimes only have to be counted at 50%. What are your experiences with this and how can I proceed to apply for these exceptions with the municipality? The kind lady there always just referred to our building application. There we are already at just under 0.4 with the maximum floor area ratio. However, it was not taken into account that certain areas only have to be counted at 50%.

Well, internet research. And/or simply misread or misinterpreted:

The permissible floor area may be exceeded by the floor areas of these facilities by up to 50%, but no more than up to a floor area ratio of 0.8; further exceedances of a minor extent may be permitted. [...] In this case I understand it as that I only have to count 50% of our garage as well as of our yard. Thus I would gain about 90 square meters.

That the areas used for driveways & co. may "exceed the actual remaining space available for them by 50%" is something completely different than that they should only be counted at 50%. Such "discounts" do exist as well, but as special exceptions explicitly named and quantified in the development plan in connection with certain construction methods (for example, to appropriately take into account that grass-grid stones do not cause full sealing).

If I look at other houses in our street, especially multi-family houses for rent, there must be valid exceptions here. Because definitely more than 50% of these properties have been built over.

It also says there that exceedances within the mentioned extent may be permitted. Consider how you could carry out such re-naturalizations of sealed surfaces! For the new paths, I would think about alternatives from the start (bound gravel paths or similar). You don’t have to concrete or pave every walking surface.

That the areas used for driveways & co. are allowed to exceed the actually available remaining area "by 50%" is something completely different from the fact that they would only be counted at 50% or should be.

You are right. But for me, it comes down to the same thing because of the sentence in the building regulations.

The permissible floor area may be exceeded by up to 50% by the floor areas of these installations

Let's say I have, for example, built 0.35 of the area without garage and yard and only add the yard and garage at the end. That way, I can arrive at a floor area ratio (FAR) of, for example, 0.5 without there being any problems, right? So I don't just count the areas at half value, but only add the areas at the end to then legally exceed the area of 0.4?

No further notes on the floor area ratio are made in the plan.

That’s not what I meant either. But you refer to multi-family houses and their development, and these are not allowed here at all (except possibly semi-detached houses with two residential units each). So a different development plan probably applies there. You can’t refer to that. But whatever.

From the building regulations

Again: the building code is fixed! It depends on what is stated in the development plan. The development plan refers to the building code in the textual specification, but that varies in each development plan. Otherwise, there would be no need for a development plan.

Have a look here, you need to read the text, and read it carefully.

I also spoke with the municipality specifically

Sorry that they can’t have an overview of every single line of a development plan on the phone or so ad hoc, nor can they verify everything immediately.

to make everything compliant

For that, they also need your property as it is built. As already said!
You can’t just throw out what you want to refer or claim to.