Map generic family instances to IFC containers (element types) before exporting a Revit project to IFC.
You can do this by creating a new IFC mapping file or editing an existing one. Also, you can use the following procedure to load the desired IFC mapping file before exporting a Revit project to IFC.
To load and modify an IFC mapping file
Revit creates an IFC mapping file named exportlayers-ifc-IAI.txt.
Each row in the dialog represents an element category or subcategory. For standard building elements, an assigned class name appears in the IFC Class Name column. For building elements that do not have automatic mapping to IFC export classes, the value displayed in the IFC Class Name column is Not Exported.
Appropriate values are set according to the IFC standard definition. Selecting Not Exported prevents elements of that category or subcategory from being exported.
If the values for a category or subcategory are blank, Revit will try to determine the appropriate category. If a match cannot be found for an object that has geometry, it is exported as a proxy object.
When you export a Revit project to IFC, Revit automatically uses the appropriate IFC mapping file.