Calculation for a single-family house with 175m² living area, basement, and double garage

Long live the digital authority!

We have become aware of a problem

Who is "we"? If that includes the architect, he could be the problem.

maximum one story

correct

or 1.5 stories

Half stories do not exist under building law.

Kniestock 60 CM

wrong

Roof pitch 30 degrees

more precisely maximum 30°, minimum 28°

The restriction does not apply to the other parcels and houses in the area.

wrong

Why are individual parcels explicitly "restricted" by the development plan?

This is a misinterpretation that correctly clarified in #39.

Kniestock maximum 60 CM

... refers to the WR areas with the superscript zero, that is northeast of the sports park and west of the 5th amendment. This restriction does not apply to the red-marked plots in your excerpt.

Yes, I am. I have asked the relevant neighbors.

What roof pitches do they have?

but not something analogously citizen-friendly like a simple PDF

Click on the map, click on the info button in the box "Linked Documents" at the bottom of the window that opens, and click on "[Download]". Actually very informative, unfortunately only the reasoning for the changes has been stored, so that the reasoning for the original plan, whose stipulations mostly still apply, is not accessible.

Who is "us"? If that includes the architect, he could be the problem.

"Us" is my wife and me. We initially focused on the knee wall, which in itself was not yet a problem. Or rather, it would have been a problem that we would have accepted. Only in combination with the roof pitch did it seem to become a deal-breaker. The architect, after what I said was loose contact, planned something that was oriented to the 60 cm knee wall and 30 degree roof pitch. This made us realize that this actually seems to be a bigger restriction than previously thought. We then consciously drove along the street again and found out that the house opposite (and the house next door) are apparently and after consulting with the respective owners built differently. Therefore, admittedly as amateurs, I took another look at the development plan and asked myself the question "Why?"

... refers to the WR areas with the superscript zero, i.e. northeast of the sports park and west of the 5th amendment. This restriction does not apply to the red-marked plots in your excerpt.

That’s it! The penny is finally dropping. That was the crucial hint. That means, simply put, that for our targeted plot there are no "special" restrictions regarding the knee wall (so "only" the "usual" ones in the development plan), but only regarding the roof pitch?

What roof pitches do they have?

I hadn’t (yet) questioned the roof pitch until now. But the knee wall. The neighbor right next door and the neighbor directly opposite both said they each have a 1 meter knee wall.

Why does my professional colleague not override the roof pitch/knee wall over dormers?
Furthermore, there is the possibility to apply for a deviation from the development plan.

In addition, a second "KfW55 residential unit" should be created so that the funding amount can be doubled. Whether the house is approved as a single-family house often does not matter.

I would consult another colleague besides the previous architect here. For such a construction project, I would expect a bit more "creativity" from the client.

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Note: I only read the EP and the last page.

The fact is, the surrounding plots including buildings (e.g. right next door or opposite) definitely have different roof pitches and knee wall heights.

I had (not) yet questioned the roof pitch so far.

You should work a bit on the precision of your wording; apparently there is a surveyor who always takes it terribly precisely here .

for our intended plot

We don’t know that yet. By the process of elimination, only plot 499 really remains, but you haven’t revealed it so far.

so "only" the "usual ones" in the development plan

Which ones do you mean?

The neighbor right next door and the neighbor directly opposite each had, according to their own statements, a 1 meter knee wall.

So it rather looks like the neighbors have built conforming to the development plan.

Avoiding slopes with a 30° roof pitch and only one permitted full floor is not that easy. How much knee wall is possible depends on several factors that the architect has to weigh based on your wishes. However, the 60 cm limit does not have to be observed in this development plan area.

Avoiding slants with a 30° roof pitch and only one permissible full floor is not quite easy. How much knee wall is possible depends on several factors that the architect must weigh based on your wishes. However, the 60 cm limit does not have to be observed in this development plan area.

... rather the restriction that the attic is supposed to be what is popularly called a "half" floor, i.e., from a certain point onwards, any increase in roof pitch would be regretted by a decrease in knee wall height.