Workflow architectual model -> BEM (Flatten IFC objects)
I am trying to find a flexible process to convert architectural models to something that can be used for building energy simulations. The only information I am interested in right now is geometry, most importantly floors, windows, and roof.
I have not access to the original files that are usually drawn in Rhino or Archicad and rely on exported files from the architect, usually IFC-files. Unfortunately, I seldom have the possibility to get in direct contact with the architect so the IFC usually are not very suitable for building simulations.
Anyway, my idea now is to find a way to convert the IFC-files into flat surfaces that can be used for BEM-simulations. My current workflow is to convert the IFC-files into a number of OBJ-files. This works surprisingly well, but the problem is that I have not find a way to flatten the almost 2-dimensional objects like walls, windows and floors. My second idea is to convert the IFC-files to gbXML before I convert them to OBJ. I think this would be a good method but unfortunately, I have not found a method to do this.
Any suggestions would be useful, including usage of Openstudio, BIM-server, XMLTOHB, IFC-to-gbXML-converter, Spider and/or IfcOpenShell.