Missing properties when exporting IFC from Revit using custom property set mapping TXT file

[Howie_Liu]

Hi, I am exporting IFC from Revit and trying to group the parameters (include the built-in and user-added). I used the attached TXT property mapping file and ticked the option in the image. 

But I found that in the exported IFC model, some properties defined in the TXT file are exported but some are not. For example, only the "Absorptance" property is exported although I included other properties in the "Analytical" group in the TXT mapping file. May I know where is the problem? The Revit model and TXT mapping file are attached. The exported IFC file is https://drive.google.com/file/d/1XHLinlPZ09HLarfhc_s_RV5-jNl-5Wlk/view?usp=sharing  Thanks!

[nielsbleijenburg]

Have you found out any solution?

[Howie_Liu]

Someone said that for some missing parameters, it is due to the mismatch between the unit of the parameter in Revit and the unit of the parameter with the same name in IFC schema. For example, the IFC schema has a parameter called "Roughness" (doc ) which doesn't match the units of the parameter in Revit called "Roughness". As a workaround for such parameters specifically, maybe create a new parameter with a different name in Revit and then map it to Roughness in IFC (or keep the new name). 

For some other missing parameters, they are grayed out which will not appear as they don't have any value. 

I haven't tried and validate this solution. Just FYI. Hope it's helpful.