Propertyset duplicates in IFC-data

[teemu.kangasmakiRSGGS]

I suppose that this concern have already issued here, but I couldn´t find the discussion via find.

From multiple projects we´ve encountered the issue where we should implement data from IFC and the situation is that some of the data, supposed to be on PropertySet - Identity Data, is either on Identity Data or Identity Data (Type).  With this current situation it is almost impossible to make any working QTO´s in any solution that is utilizing / working on the basis of IFC, not the native formats like RVT.

What is the logic behind the fact that Revit produces PropertySet-duplicates for IFC-data and how I could prevent this happening? There seems to be no logic behind the situation where some of the model categories provide duplicates and some categories don´t.

PLEASE help me.

[L.Maas]

I think the logic is as follows. Revit makes use of instance and type parameters. That is why you see the split sometimes. In Revit it could be theoretically possble (not desired) that you have two the same parameters name, one as instance and one as type. So if you would combine them together in a single set than you would end up with two the same parameter names. The question would become, what do you do in the export? Take only one, or rename one or....? To prevent data loss this can be solved by using the two sets (with or without type).

During Export did you select "Export Revit Proeprty Sets"? It is one of the setting better to avoid (to overload the export with unnedeed data).

You better can make use of "User defined property sets". Then you can control exactly which parameters will be exported and to which set name.

[kh_jea]

I'm a little late to the party, but I want to add the the addition of (Type) seems to a at random as well. Assembly Code for instance is always a Type parameter, yet it appears under "Identity Data" and "Identity Data(Type)".

Somehow autodesk can't even export their native parameters correct (not that I'm very surprised).

On top of that mapped shared parameters will show both under the mapped name as the original name.

[teemu.kangasmakiRSGGS]

The logic does not follow the split between instance & type parameters as you explained. It might seem like that with the study of one or two models, but when expanding the scope there´s absolutely no logic. I´ve tried out the modelling with different scenarios.

Of course we´ve tried to create as fool proof User Defined Property Sets -mapping but the problem is that we are a developer & main contractor and trying to implement & enable the data from the designers, not designing by ourselves.

We have yearly approx 100 running projects from approx same amount of different design disciplines who - by nature - use the (different) authoring tools very different from each other. We deliver our IFC-exporters & supplementary files for them, but can´t foresee all the used families with hundreds of used parameters, so there will definately be the need of "Export Revit Property Sets" as well. When the mapping fails, we still have to find the needed data from some where.

Still holding my fingers crossed that Autodesk will focus on developing the IFC since that is the most used format in The old continent, especially in Finland.