In your domain model, you put your room as a generalization of a building, this is why you have that behaviour, you just have to remove the generalization
Things I do not get to work unless I have a generalization:
- reference selector (no possibility to add building in tasks)
-validation rules (I want total number_of_floors to be greater of equal to the floor_number and same for rooms)
I feel like there is still something that I do not understand about how data is inherited. There is often a situation where I want to use an attribute from an associated entity but am not able to.