Cost estimation for demolition and new construction

By "connections don't fit," do you mean that if insulation is added, something also has to be done to the roof overhang?

I mean, if high-quality insulation is used, nothing needs to be done to the roof overhang. Re-roofing also has nothing to do with it.
However, if you WOULD LIKE to enlarge the overhang, then a new roofing might also be worthwhile. You could still insulate regardless.

We have been thinking about the house again these days. The fact is, the location is great and we like the existing house (you have already seen the photo).

The fact is also that we find the shoebox extension terrible. But we need the space. So the extension either has to be accepted as it is or changed.

Removing the extension and simply expanding the house by 2 meters (up and down) is probably too simplistic and impossible because of the exterior wall.

I am now attaching the plan of the ground floor and hope for tips and ideas.

And if someone of you can recognize from the floor plan which walls are probably load-bearing, that would also be helpful.

So I’m attaching the plan of the ground floor now and hoping for tips and ideas.
And if any of you can tell from the floor plan which walls are likely to be load-bearing, that would also be helpful.

What does the dashed line represent?
I see absolutely no load-bearing interior wall there, which is an indication of a wooden beam ceiling (which then can’t carry much additional load, so improving impact sound insulation is out of the question). Several walls will be bracing, though.

What does the dashed line represent? I see no load-bearing interior wall there, which is an indication of a wooden beam ceiling (which then also cannot bear much load, so you can forget about improving impact sound insulation). Several walls, however, will be bracing.

The dashed line on the left is the garage (more like a better bicycle shed with less than 3 m driveway width). The small square next to it is the basement stairs.

You confuse me with the wooden ceiling and impact sound insulation. My parents' house also has wooden ceilings.

On the right is a roof overhang/terrace roof.

Regarding wooden ceilings: Are there typical thicknesses I can look for in the house cross-section that distinguish them from concrete ceilings (were they regularly used in single-family homes in 1960)?

Regarding wooden ceilings: Are there typical thicknesses that I can look for in the cross-section of the house that differentiate them from concrete ceilings (was that regularly used in single-family homes in 1960)?

If you have more drawings, bring them on. The wall thicknesses here are a clear contraindication against a concrete or other heavy ceiling, and 1960 for such a small settlement house is also still to be counted as post-war period. By the way, I don't like the many chimney flues either, what kind of heating is in there?

If you have more drawings, then bring them on. The wall thicknesses here are a clear contraindication against a concrete or any other heavy ceiling, and 1960 is also to be classified as post-war period for such a small settlement house. By the way, I don’t like the many chimney flues either, what kind of heating is in there?

What could the chimney flues (4?) mean? The type of heating can only be guessed since the inspector was not allowed in. He estimates that it is an oil heating system that has possibly never been replaced. Can that really be, a heating system that has been working since 1960?
I could also imagine that something was done to the heating during the extension in the 70s.

The two cross-sections available to me. One from 1959/1960 and the other was created in the 70s during the extension.