The Timber Roof Framing Extension and Structure Generator Extension are now avaialble for Revit 2013! You can download them on the Subscription Center.
From Bim and Beam:
"Roof Framing Extensions for Autodesk Revit 2013 software applications is comprised of two extensions that help automate modeling of roofs in Autodesk Revit software.
The Rafter Framing extension enables the definition and generation of various types of “A” frame roof models.
Another extension creates truss roof systems.
Structural elements are created based on a selected Revit native roof object. Generated timber roof structures can be exported to Autodesk® Robot® Structural Analysis Professional software to perform further structural analysis and design tasks.
Structure Generator Extension for Autodesk Revit 2013 extension helps in creating different variants of architectural models and verifying them from structural point of view. The extension helps to coordinate models between the architect and structural engineer and can help reduce the number of changes required in the model during the later phases of design."