Product:	OpenBuildings Designer
	Version:	CONNECT Edition
	Area:	Import/Export
	Subarea:	IFC

Problem Description: 

I want the Space Description in my exported IFC file to contain the info from "Label2", or possibly other attributes when it's populated and empty otherwise. How can I get these results?

Steps to Accomplish: 

The IFC properties are mapped to the DataGroup properties using *.set files. In the Dataset_XX/Setting folder, there are two files that drives the mapping: IFC_PropertyMapping.ifc2x3.set for IFC2*3 property mapping and IFC_PropertyMapping.ifc4.set for IFC4 mapping. Please follow the below steps to achieve the desired results. 

1.  Using Windows File Explorer, navigate to the desired Dataset/Settings folder and open either of the two files mentioned above. For example, I am opening IFC_PropertyMapping.ifc4.set.

2.  Scroll down to line 44 where it has been stated Space * * Description * ArchSpace/@label



    
3. To change the output in the IFC file you need to change this line to get desired result. Modify the line to Space * * Description * EVALUATE FirstDefined (DG("ArchSpace/@label2"), " "). This will look for Label2 value first, but if not found then will leave that field as empty.   
                                           
 

4. After performing these changes, launch OpenBuildings Designer and export the space(s) to IFC and you should see the changes in the description field.