House Renovation Construction Year 1955/1974 - Estimation and Feasibility

But were the other houses also once small plus a chicken coop, then expanded to a larger house and only afterwards extended upwards? If that is the case, then you should talk to the neighbors who have experience with architects and companies in this area. That could significantly speed up the search for suitable partners.

I just searched for pictures on the internet. The settlement was founded in 1936 and at least the houses built at that time were similarly small but each had one more floor. Anyway, I wanted to talk to a neighbor since he is currently completely renovating his house.

I had mentally already included the extension on the upper floor. If I’m not mistaken, you have a height of 1.70 m in the middle of the room.

Just to clarify the terms: an extension would be placing a complete additional storey and, in my estimation, here then with a new roof structure. With a knee wall to just raise the roof and/or have it slope more gently, I see this rather unlikely due to structural reasons.

Of course, if everything is being opened up anyway, I would run Cat-6 cables in parallel and bundle them in a large VLAN-capable switch. [...] Further extending the house is therefore also out of the question, since otherwise the 16m privilege in Bavaria would no longer apply. Here the eaves height from the natural ground boundary applies, right?

Without knowing the Bavarian 16m privilege in detail: I don’t understand your reference to the ground surface edge in this context. Incidentally, "VLAN" is a term from modern times – but you will only get this property modernized to the standard of 1990 with reasonable effort. In this respect, in my opinion, you are in the wrong mindset or are clearly undertaking a renovation for personal interest. Talking to the neighbors about their experiences strikes me as the most sensible idea in this whole scenario. Whether a new building could be positioned significantly differently, I mark with a question mark. This could be opposed by “factual building envelopes” – that is, the zone indicating how far the neighboring buildings are set back from the street.

I wanted to talk to a neighbor anyway, as he is currently completely renovating his house.

Good start. And then specifically look for an expert in old building renovation. As already mentioned, it usually concerns (large) bourgeois houses from the Gründerzeit, etc. The rather small-town settlement houses should probably be especially checked with regard to their actual substance. And modern residential aspects should also be considered. Larger rooms, no small staircases, ceiling heights, etc. In a good location and with good ideas, you can often make a lot out of it, but unfortunately just as often the property without the old building would simply be more suitable. There is a reason why people talk about the lifespan of buildings. And just because historically built houses from the pre-industrial era still stand doesn’t mean this applies to everything that was built 80 - 50 years ago. Without the current market situation, one would in my opinion tear down and rebuild significantly more.