How do you want to obtain a building permit? Normally, you coordinate it with the neighbors, draw the submission plan accordingly, and then submit it with an exemption to the municipality and district office.
Smart urban planners take such terrain conditions into account in the development plan. Check whether there are regulations allowing a determination of the wall height that deviates from the state building code. If not, but there is agreement with the neighbor: deviation according to §69 State Building Code. If things go really badly, encumbrance according to §86 State Building Code.
How does such a waiver procedure work?
You present the site plan and the construction drawings to the neighbor for signature, and your designer fills out the form "Deviations from building supervisory requirements" in addition to the other planning documents. The registration of encumbrances works similarly. Since I consider the necessity unlikely here, ask the approval authority about the formalities when you inquire about the reasons for rejection of the deviation application.
Hello everyone, to pick up the topic again: If I keep the average wall height of 3.20m and slope the roof at 45 degrees from this height until the desired height is reached, then the roof sloped at 45 degrees is not counted towards the average wall height at the boundary, right?