Build a sheet metal hall on the border

Hello forum,
my name is Rainer and I have a question. I built a small hall 10 years ago, 13 m long, 3 m wide, and 3 m high, made of cheap trapezoidal sheets. My neighbor agreed. But since it leaks a lot, I wanted to rebuild it. Everything with ground sleeves, beams, and sheet metal.
This time, however, I want to be on the safe side. I need 4 m height, 8 m length, and 4 m width this time.
Am I allowed to build that? Possibly with a pitched roof because of the height.

Thank you very much for your help.

Thanks in advance

My layman's opinion is that your current hall is an illegal construction and the new one would be as well, since it is, in my humble opinion, subject to approval (over 40m³ volume). The old hall was also located 13m on the boundary, 9m (in total) are permitted.

Please excuse me, I expected such an answer. But that was not my question... I would like to ask you to answer only my question. I know about illegal construction myself and do not need the previous comment.

I want to remind you that you asked in the initial post whether you are allowed to build that, therefore answered your exact question, even with a justification! Regards, Yvonne

Please excuse me, I was expecting such an answer. But that was not my question...

May I build that?

Exactly that was your question. Another one cannot be found.

and I do not need the previous comment

Consider it a gift.

Hm, I understand the question from the OP "Am I allowed to build this?" referring to the new, planned hall with 4x4x8m and not to the old, current hall. He could also have written: "Am I allowed to build a hall with the dimensions 4mx4mx8m, where the 8m side would be on the boundary?". However, Alex85's answer referred, in my understanding, to the old hall.

PS: Apart from that, the OP could certainly have expressed himself more politely in his reply/reaction to Alex's post and, if he expects further helpful answers, even should have.