I often get the question why not all parameters defined in the IFC schema are not part of Revit? Since many of these parameters are not useful for every project and vary depending on the use case, the usual standard properties are populated directly from Revit - but additional properties can be added manually at any time.
To facilitate this process, the text files with the shared parameters are also supplied with the installation - these contain all the PSets defined in IFC and supported by Revit:
If the properties are added to the project and populated, they are also exported automatically.
The most important properties for the IFC export can be found in the Revit IFC Exporter Parameters group, but all other PSets and the available properties can also be accessed in the drop-down.
Note: Some of these properties allow you to overwrite the default values, such as IfcName - this parameter overwrites the name of Revit families during export, for example.
Actually, these properties do not have to be added from the supplied text file, it is only important that they have the correct spelling and data type. Nevertheless, it makes sense to manage them as shared parameters so that their ID remains the same across projects.
You can find out more about the shared parameters in the Autodesk IFC Manual.
By the way, if you can't find the text files on your hard disk, you can also download them from Github:
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