This is a brief summary of some of the major changes in the R2013 version of the IFC export for Revit project.
o Much more access to code: We've quadrupled the .NET code base in R2013 from R2012, allowing for much greater customization abilities.
o Support for future IFC formats: In conjunction with the IFC exporter alternate UI project, a user can supply their own EXPRESS (.exp) file corresponding to an alternate or future version of IFC, and write routines to support that version in R2013.
o Capability to add export of any IFC entity: Unlike in R2012, R2013 allows the generic export of any IFC entity. This means that users can add concepts that are not native to Revit, or that have yet to be implemented.
o Solid faceter: The number of surface models created in R2013 has been significantly reduced with the addition of the solid faceter, making the Revit output more usable in downstream applications.
o MEP connector support: MEP Connectors are now exported, with the exception of Electrical connectors.
o Sharing of geoemtry for MEP elements: Family-based MEP elements now share geometry via Mapped items instead of getting separate geometries. This can greatly reduce file size for files with many curved MEP elements of the same family.
o Many bug fixes: We greatly improved the quality of the export by fixing hundreds of bugs in the R2013 release.
We hope you enjoy these improvements and happy customization!