Approval of boundary construction in case of partial roof extension

Can you show the site plan with the relevant neighboring buildings? Is that the neighbor in the background?

The approval is granted by the building authority. You should inquire whether your project can be approved. They also understand what you mean. Unfortunately, I do not so far.

Is that the street front?

I think today I am simply unable to explain clearly what I want.

The house is a rear building and the roof slopes towards a passageway with very little traffic. The building consultation says that I have to get the approval of the neighbors, but a roof terrace was also considered here, which does not necessarily have to be realized.

The neighbors probably do not want to give their consent; there is a complicated owners' association here... unfortunately. I am now trying to find out what is possible without consent.