In the latest versions of the Revit IFC Exporter, there have been some changes that lead to a different behavior when exporting Revit type parameters.
In IFC - as in Revit - there are types and instances for most entities. In the past, the Revit IFC Exporter "forgave" an incorrect assignment in the configuration files, but due to various adjustments and general improvements to the IFC Exporter, this is no longer possible in newer versions, which means that the following must be observed in the configuration file for user-defined property sets (DefaultUserDefinedParameterSets.txt):
For the export of type parameters, it is no longer sufficient to specify the IFC class, e.g. IfcElement or IfcWall, but is mandatory to specify the type (e.g. IfcElementType or IfcWallType).
Attention: Unfortunately, doors and windows do not have types in IFC 2×3, but styles, which is why IfcDoorStyle or IfcWindowStyle must be specified here.
In IFC 4, on the other hand, IfcDoorType or IfcWindowType is used.
Here is an example:
Line 1:
Test = Name of my property set
T = actually stands for I (instance or copy) or T (type), but no longer has any functionality, but must be specified for the time being. Important: Regardless of this specification, both instance and type properties can be specified in the same property set
IfcWall, IfcWallType, IfcDoor, IfcDoorStyle = List of entities to which the property set is assigned
Line 2:
Test property: Name of the property in IFC
Text: Data type (should be the same in Revit and IFC)
Optional: in the third column, the name of the Revit property can be specified if it is not the same as in the IFC
Result: The property set is created on all walls and doors and filled with the specified specimen and type properties.
Reminder:
IfcElement or IfcElementType creates the property set on all visible elements, this can be restricted by specifying IfcBuildingElement or an explicit entity and different entities can also be specified separated by ,:
The corresponding setting and the link to the configuration file can be found here:
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This post has helped me solve some issues I've been struggling with lately.
Great! Thank you very much for this information. Now the whole IFC mapping finally makes sense
Hi
I'm struggling with exporting parameters using user-defind property sets. In my case for some reasonsparameters of type aren't exported, but instance parameters export very well. It doesn't seem like T/I setting does anything at all. In both cases (T or I) instance parameters are exported and type doesn't.
Does anybody have an opinion on this>
Thanks
Hi Lejla
First thank you some great posts and videos.
I have been successful with creating User Defined Property Sets over many years. But now somthing is not working. I can not assign the Type Name of Curtain Wall Panels (Door Component) to my User Defined Pset. This is the mapping details:
PropertySet: Pset_KK I IfcElement, IfcElementType
Type Text Type Name
I have did try with IfcRoot as element first but, did not work so i shifted to IfcElement, IfcElementType but still no luck. Can you explain what's going on her?
Regards
Peter
FollowUp
I found the error in the Family, there was added a parameter in the family called TypeName, although it is not completly the same as Type Name with space, it causes the exporter not to Export the builtIn Type Name. I will create an issue on GitHub.