Teun De Vries shared an: “Excel document (download), with which you can build the mapping tables that Revit can use when importing from, or exporting to IFC. It is still a bèta. You can use it or even change it, but at your own risk of course. And if you do so, Teun would love to know what your experiences are. The RevitGG is also using this tool to help build some parts for in the Dutch Revit Standard the DRS.”

Original post:
Ik Leer BIM: A tool to build Revit’s IFC mapping tables

Looks pretty interesting?

“Revit makes available the following IFC-specific files:

  • IFC Metric Template.rte. This file allows you to create new projects that are already set to the IFC standard.
  • IFC Parameter Upgrade.rvt. This file enables you to upgrade an existing project to contain IFC parameters by reading the instructions contained in the IFC Parameter Upgrade.rvt file.
  • IFC Shared Parameters.txt. This file contains the shared IFC parameters if you want to manually update an existing project to contain all or some of these parameters.
    Note: It is recommended that you use the IFC Parameter Upgrade.rvt file. If you use IFC Shared Parameters.txt, you must add parameters one at a time, setting the correct categories for each. If you use IFC Parameter Upgrade.rvt, you can use the Transfer Project Standards tool to add the parameters in one operation.”

From Help: Access IFC-Specific Files

It will send you here:
http://revit.autodesk.com/library/html/index.html

And you can download IFC.exe from this direct link
which contains these files: