Architects can design buildings in Revit, then export the relevant building content as a 3D model to civil engineering applications that accept Autodesk Exchange (ADSK) files, such as AutoCAD® Civil 3D®.
To export a 3D building site to an ADSK file
- Prepare the building site for export.
- Create a 3D view and reduce the complexity of the model in this view so that only the relevant elements are visible. See About Preparing the Building Site for Export.
- Create one or more area plans, and optionally, property lines for the building site. One of the area plans must be designated as the gross building plan that is exported as the building footprint. See About Creating Gross Building Areas and Property Lines.
- Create relevant site utilities with host connectors that are functional in the civil engineering application.
Note: Only those site utilities with connectors that have the Utility parameter selected are exported.
- Click File tab
Export 
(Building Site).
To export a building site, you must specify a gross building area. If you did not create a gross building area previously, you are given the option of creating one now, and then must repeat the Export command.
- Review the export settings in the Building Site Export Settings dialog. See About Export Settings for a Building Site.
- Click Export to save the building site as an ADSK file.
In the Export Building Site dialog, verify that View Export Report in Default Browser is selected. This option lets you view the export report in your default Web browser.
- Review the Export Building Site report. See About Reviewing the Export Report and Delivering the Results.
- Deliver the ADSK file to the civil engineer.