In my opinion there are several ways to handle the clasification of balcony slabs (and other components that cannot be further classified by enumeration):
clasify the balcony slab as Ifcslab with the predefinedtype “FLOOR” and distinguish it by adding “balcony” in the name of the element
clasify the balcony slab as Ifcslab with the predefined type “USEREDFINED” and distinguish it by adding “balcony” in the name of the element
clasify the balcony slab as Ifcslab with the predefined type “FLOOR” and distinguish it by adding “balcony” in an additional created attribute like balcony (true or false)
In your opinion which is the best way to handle the information of these elements. Do you know a better way?
We have this example in most of our projects. To be honest our workaround is like you describe in Nr. 1, which is actually the simplest one. I personaly don’t see it as a floor component even though it is in the same level as the slab of the floor. It is not the cleanest way of defining this parameter.
A better way would be to have an additional IfcSlab TypeEnumeration just for balconies. Why?
These elements are in most cases precast whereas a slab in many cases is cast-in-place concrete. Structuraly speaking, they are also seperated from the structural floor, which makes them unique elements. In the aspect of building physics, they don’t belong to the internal components and don’t build the thermal envelope.
Therefore, having in the future an additional parameter would help here to resolve many cases.