Thanks for posting Ian. I’d personally like to see many of these points be specifically discussed in their own threads (and I’ve referred or started some to the points I refer to below).
I think it’s fair that serialization has had a huge influence on the design (given it originated over 20 years ago) and that modernizing IFC will cause change. You can find some of my thoughts here: Industry Foundation Classes are a Data Schema, not a file format
I recall that I raised the model archive point in the technical room discussion in New York. 2GB ifc files should be scrutinized and implementations or models generating them should be altered.
This thread touches on the topic, IFC Backwards compatibility
There are constraints within the schema and “Implementer Agreements” that direct this scenario for IFC2x3 (and earlier I presume). These are better handled be specifc MVDs (that might be extensions of the official ones) for IFC4 and beyond . Certainly a lot of infrastructure projects won’t have a building.
I’d personally like to see a specific thread on this topic, and I started one here: IFC Modernization : Relationships
This should also be discussed in a specific thread. As previously discussed, maybe there is an alternative superior choice although I don’t see it being json (as it doesn’t have official provision for common references, so this needs to be thought through).
This isn’t one I feel so strongly about, with the Ifc prefix you don’t get class name clashes when developing with an API (such as Revit or Tekla). If there is consensus on this certainly the schema to toolkit approach can be configured even if the serialization doesn’t change.
This actually already exists even if it’s not readily apparent. It’s certainly not evident in the long form version of the express schema and not in the xml. You can see it in the short form schemas.
I want the buildingSMART toolkit code relocated ASAP, but you can see evidence of the namespaces here: https://github.com/buildingSMART/IfcDoc/tree/master/IfcKit/schemas/IfcHvacDomain
I’d like to see serious improvements in this. To my mind the XSD schema needs to be improved but already I do use XML for schema validation without IFC specific tools. MVD can nominate requirements/constraints above and beyond schema and I’m not sure these can be captured in XSD. I’d also refer to this discussion. How to validate an IFC4 against an mvdxml