Ideas for floor plan adjustment of house with extension on the west slope

I believe the extension already exists (it would also be interesting to know here whether it is insulated, what kind of windows etc., same level as the existing building, is the entrance lower, meaning a raised ground floor, which was often the case in 1955...) and is to be renovated as well.

Why is demolition not up for discussion?

The extension already exists and dates from 1957. It is intended to be used exclusively by the EG apartment. Insulation and windows are therefore roughly similar to those of the rest of the house. The entrance is at the same level as the EG and the extension. Demolition is not an option, as it currently seems too expensive for us to rebuild. Maybe we will simply keep the floor plan as it is and use the entire house ourselves. Then some rooms will just remain empty. I just thought that other people might have more experience here and see possibilities in the existing floor plan.

It's simply a classic floor plan from that time - but what that also means is: if you do a full renovation and remodel, nobody really wants that anymore. And often, unfortunately, you don't know what to expect during a full renovation. I'll say worst case: there was a massive water damage that was never properly fixed and the mold has been sitting in the wall for years. Or God knows what. The foundation slab is water-permeable, etc. There are many unpleasant possibilities that you only discover during the renovation. Moreover, the requirements for electrical and plumbing systems are totally different now compared to 1955. That means if you want to do it right and well, it involves a huge effort just to be reasonably up to date. The extension is not basemented and is from 1957 - so I assume the floor slab isn’t insulated either, meaning the floor is likely always relatively cold. If you don’t want that, it becomes really elaborate. Etc. pp. Overall a lot of work (and costs) with an uncertainty factor that no one really wants or can name. Therefore, a full renovation should be very carefully considered. It won't be much cheaper than demolition and (modest) new construction (you apparently don’t want to live that large). If one of the uncertainty factors hits hard, it can also be significantly more expensive - and drag on for a very long time. Then the question simply arises whether the house is worth it. We cannot judge that. Maybe it has a high sentimental value for you – which is quite legitimate, and then you are also much more willing to invest. If it doesn’t have that, if it’s not a charming little house from that era, not an exorbitantly high-quality building substance for its time, and no historic preservation applies – honestly, then I would tear it down. What is your situation like? Do you already live there? Then demolition is of course a different matter (but also with full renovation). Do you already own the plot? What is your financial situation? Would it be conceivable to first gut the interior yourselves and then only do the rough demolition afterward? And in the meantime possibly increase your equity – all possibilities. New construction is not cheap, you’re right, especially today, where everything is more expensive due to the boom. But you have facts, relatively exact numbers, and timelines. With a full renovation, all that is much vaguer. My brother renovated an old farmhouse (from the 17th century – of course with historic preservation, so already a somewhat different matter), the budget was significantly exceeded, the timeframe more than doubled. Instead of a few months, they had to live elsewhere for almost two years. And all that was UNFORESEEABLE even with appropriate experts and architects beforehand. I think before you start trying to find the best possible solution for you from the existing building, you should go into internal review again and weigh everything up. If you still say afterwards: we’re doing it, we want to do it – then there are enough people here who will work out a usable floor plan. But probably most feel like me: it’s not so clear to us why this old shack absolutely has to be preserved. I’m not sure whether demolition and building a small single-family house might not even be cheaper than converting this house into two residential units.

Demolition is out of the question, as it currently seems too expensive for us to build anew. Maybe we'll just keep the floor plan as it is and use the entire house ourselves.

Ok, new approach: just name your rough budget, what you are generally willing to spend. If we then end up (which I suspect) only with a small renovation anyway, you can save yourself all further worrying.

I'll put it this way: sanitary rough-in, electrical, screed, insulation, heating system, roof, facade, windows, tiles, interior plaster, and so on do not cost more in a new build than in an older building: 1m of PE pipe costs as much as 1m of PE pipe. On the contrary: if everything can be planned from scratch, much is installed faster, complicated adjustment work is eliminated, you save above all time and also some money. One example is, for instance, windows (with roller shutter box) in new build standard sizes (at least in 12.5cm steps) are cheaper to obtain than real centimeter-accurate custom-made products for your old building. Enlarging windows... you need wider lintels, which even endangers the shell construction. Shrinking windows to reach standard sizes? Who likes shrinking windows...

With what you are planning, you won't avoid a building permit even in the renovation, energy saving ordinance requirements for old buildings will be imposed, and so on.

The budget is about 200,000 euros. If something nice can be achieved for less, then of course gladly. We want to do quite a lot ourselves. A few years ago, we already renovated a house from the ground up including plumbing, electrical work, and insulation. The windows are the least of the problems, as we ourselves have a window and roller shutter construction business. Custom-made windows are standard here.

Unfortunately, I did not find an attached questionnaire.

You are also in the wrong subforum.
If you take a look under the floor plan discussions, there is one there. Without it, there are only follow-up questions.