Changes to the house and floor plan after submitting the building application

Hello,
just a general question, although it doesn’t directly concern me at the moment, it’s interesting to know. It is assumed that the building application has been submitted: What am I still allowed to change now without the building application having to be reviewed again?
Of course, major things are probably clear – especially things that affect the structural engineering, legal requirements, design statutes, etc.
Also smaller things, like a bedroom now becomes a children’s room or a door no longer opens to the left but to the right, and so on.
I’m more interested in such things that are not so clear. Maybe a kind of list can be compiled here as a general overview.
I am specifically interested in:
- The installation spacing of the heating pipes for the underfloor heating
- Change of the heating system from gas/condensing boiler to air heat pump
- Location of the house (e.g., 3m further back or forward)
- Garage no longer one large room but now two rooms separated by a wall
- Additional window in a room

It would be nice if others participate here (also from experience) and a small overview is created. It might be interesting for one or the other.

My assumption: Change of house location in the countryside: No Additional window: okay Garage inside is okay, but outside is not. If there is a garage in the application, you cannot just put 2 there. Heating: no. You forfeit the energy calculation that belongs to the approval.

Roughly: everything that has external impact and influence must not be changed. Moving a window by 10 cm is okay, not by one meter. However, moving the entire building structure should be self-explanatory as a no-go if you have ever seen a site plan.

In short, regards

The energy calculation that belongs to the application is forfeited?? Well, good thing we only commissioned it three months after the approval. and the building authority didn’t even care. Since some things can indeed be state law or "municipal law" (e.g. requirement from the development plan regarding the facade color), I wouldn’t compile a hodgepodge here that might no longer apply in another federal state or even the neighboring municipality. And basically, the architect/planner should always be able to say what is possible without revision in the specific case?!

On page three of our building application, the energy office certifies that the calculation has been carried out in compliance with the legal requirements. In the appendix Building description belonging to the application, the heating type is queried and entered there. So, that is how it is in SH.

First of all, in general: your hypothetical case is so common in reality that there has long been a routine for it - the Google keyword is "Tekturklappe".

Room usage swap)
Bedroom against children's room is a private matter, workshop against living space would be something else

Change of door swing)
a matter of taste, legally not relevant - possible exception: an emergency exit door.

Spacing of heating pipes)
only comes up in the execution planning, not in the approval planning

Change of heating system)
probably an issue in the energy saving ordinance era, would not have interested anyone before

Position of the house on the plot)
is essentially part of the approval consideration

Garage suddenly desired with partition wall)
a matter of taste, the other way around it could be different (partition wall was planned, required for fire protection)

One more window in the facade)
a change requiring approval, hopeless in a firewall, otherwise usually a formality

Nationwide valid collection)
impossible with sixteen state building codes or always "without guarantee".