Adding more information when exporting IFC

When I use IFC exporting tools such as IFC manager I find the information always loose. For example, if I use IFC manager to export a single wall and open it in revit, I find that the only feature of the “wall” is that the category column shows it is a “wall”type, but the “wall” cannot be edited in the right way. For example, it cannot be assigned to a certain family and the thickness can be changed .I read the IFC document and find that in order to add the feature of “thickness” the information below needed to be added.

And I also learned that using set_classification_value method to set certain key value of certain dictionary in ruby api can add IFC information in skethup model. The question is to add such information which dictionary and key value should I set?

What exactly do you want to do with the IFC export in Revit? This is not entirely clear to me.

If you use the IFC manager extension you can create your own propertyset.
Create ‘custom’ parameters in the component attributes by naming the parameter as follows:

Pset_ < propertyset name > _ < parameter name >

In addition, you can enter the standard IFC parameters if you have classified the component / object via the component options.

Note: SketchUp Pro 2019 currently only supports IFC2x3 import and export.

For more information about the IFC 2x3 schema, view this website from BuildingSMART.
https://standards.buildingsmart.org/IFC/RELEASE/IFC2x3/FINAL/HTML/
It is a very technical page (dictionary), but here you can find all entities and related information.

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Thank you for your answer, I check the IFC2x Model Implementation Guide and find that wall in IFC can be divided into “standard wall” and “specific wall” ,a big difference between the two kinds of wall is that the shape of a “standard wall” is formed by “extruded” method while the shape of a “specific wall” is formed by “brep” method. When we export a wall in sketchup, although we choose the wall type as IFC " standard wall " in classifier toolbar in sketchup, the ifc we exported shows that it is formed by “brep” method , that is ,it turns out to be a “specific wall”!


I think the reason for this is much likely the sketchup model is shaped in “brep” method , as a reason for this, no matter you choose a wall as a standard wall or a specific wall , the exported ifc file shows it is shaped in “brep” manner, that is a specific wall.
The reason why I am so focusing on this is that in revit , a standard wall can be editted as a wall family , but specific wall not.

I have tried IFC between Archicad, Revit and SketchUp and none of the combinations have resulted result to useful editable objects. Revit uses solid geometry while Archicad and SketchUp use faces. Thus, a straight wall in Revit is a profile extruded but in SketchUp it is just 6 faces.

What I have tried with moderate success is to forget about IFC and import the SU model into Revit as a mass object, and then apply Revit walls etc. to the mass faces. Usually, for this, it is best to simplify your modelling to the extreme, with no wall thickness etc.

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I agree with you , for now the best way to interact between the two software is using mass object and rebuild. I am still looking for a way to export a SkethUp model to an editable file for Revit but it is very hard for they represent and shape an object in different manners.