Here's the first demonstration and example files for generating IFC from Grasshopper using the Geometry Gym plugin. This is just the beginning. IFC can be read by popular software such as ArchiCAD, Digital Project, Revit, Tekla etc etc. Download the plugin from http://www.geometrygym.com/downloads
Please try for yourself, and report all ideas, suggestions and problems.
Here's the Rhino file for the tower massing: Rhino Model
Here's the Grasshopper definition: Grasshopper Definition