Well, I'm not sure if editing afterward is really such a good idea. If someone joins the thread late (or new users in a few weeks), the posts no longer fit the opening thread and the course of the discussion is no longer comprehensible.
On the topic: The development plan does not seem to be unimportant. Does this information come from
Satteldach 35 Grad
? Then a hipped roof would not be permitted at all? Why don't you simply change the ridge direction? Is it perhaps fixed anyway in the development plan, since all the houses in the aerial photo have their gable side facing the street?
Das Baufenster ist also nur 11 m breit.
Generally, a building envelope refers to the buildable area on the property defined by building boundaries and building lines in the development plan. However, you seem to mean the maximum possible area according to building regulations and yet you are planning 11.55m wide. If sewer pipes are also supposed to lie under the path still to be surveyed, this must, IMHO, be at least 3.5m wide.
The minimum cross-section of an access road in settled areas is a total of 3.50 m
(Source: City of Hamburg, Building Inspection Service 3/2010)
A good half meter like that is not negligible, and with the tight dimensions, the roof overhang should also be considered. Is it allowed to protrude into the airspace of the access path?
Es ist sicher, können wir das jetzt bitte so als gegeben hinnehmen?
Just don't forget to anchor it in the purchase contract. Building encumbrance entries are not cheap.