Reinforced concrete columns at the corners of the bay window

We have a very simple house design. Still, on the ground floor there are 6 reinforced concrete pillars with a 24x24cm cross-section and even 8 in the knee wall on the upper floor. The ring beam is embedded 1.5 meters deep into the interior walls. Even the garage has reinforced concrete pillars at all outer corners and one in the middle of the 9-meter-long boundary wall.

So it doesn't seem to be unusual to use reinforced concrete for structural purposes.

Not allegedly, that is correct. For this purpose, they are exactly right there; at the outer corners, they would be more complicated to thermally insulate. Therefore, neither the shell builder nor the energy consultant should be surprised about it. The office dog understood it immediately :)

Ok, the position of the steel supports at the inner corners is energetically (and certainly also statically) better than at the outer corners. But are they even necessary? Interesting that quite a few have such reinforced concrete supports.

So then thin flat slab and with little steel...

No, what is common today is rather not called flat slabs. The reason lies here in the "tongue" of the slab above the bay window, whose enclosure mostly consists of windows and to which one does not want to burden that alone.

We also have that in at least one place. It was necessary next to the 4 cm thicker slab due to the statics.

Is it partially 4 cm thicker (?)

But are they even necessary? Interesting that quite a few have such reinforced concrete columns.

In the wall constructions commonly used today with bricks, which compared to solid bricks of older construction almost resemble hollow core slabs, it is probably more economical to work this in than stones of higher strength that were more commonly used before.

The exact "how" is probably subject to a "fashion change"—but the principle of incorporating beams / girders here and there (and providing them with a higher compressive bearing) is not new. In the past, panorama bay windows were built less frequently.

Is it partially 4 cm thicker (?)

No. Throughout.

, I understood that the passages refer to the large kitchen/dining/living room (although it is not unusually large), but I will ask about this during the appointment with the structural engineer on Wednesday. Our ceiling above the ground floor is now supposed to be 2 cm thicker due to structural requirements than originally planned.

I see it this way:

Our ceiling above the ground floor is now to be made 2 cm thicker for structural reasons than originally planned.

Where stronger reinforcement is needed, the concrete cover must not become thinner because of this. So, the entire ceiling (there) will be thicker then.