Is a glass box as a cozy corner financially feasible?

Is such a glass construction very expensive? Or statically and legally permitted? What do you think about it?

Even a bay window is more expensive than a straight wall. Here you have high demands on thermal bridges and airtightness. That should be planned very carefully and then executed accordingly. Yes, I believe it will be expensive. During operation, someone has to clean the glass surfaces, including the upper ones, which will preferably get dirty. That is also expensive (at least in my opinion).

I believe this is more something for show/representation than for actual use.

Alternative in new construction for average homebuilders:
- Large corner windows with a couch in front.
- Or the classic bay window.
- Conservatory on the terrace.

Or window seat - then it also becomes cozy!

So I am now leaning more towards the window seat, thank you very much for your opinions. Best regards

The idea is a typical photo beauty.

Yes, one should not base their house on the unlikely case that an architecture magazine still has a few photo pages free :-)

Why do you think this is not compatible with the energy saving ordinance

In particular at the top edge, I don’t see in the photo example how an insulating layer should find space at the transition over the inner masonry shell. From an insulation point of view, this is a bay window or roof overhang, and not "just" a window.

I don’t understand that. Why does there have to be an insulation layer there? It is glass, and it must compete with glass in the reference building there as well, not with a roof overhang made of brick, insulation, and substructure.

Certainly, it will not be entirely easy (cheap), but also not critical.