During CAD-to-BIM transition period it was usual practice to use AutoCAD software together with Revit in a BIM workflow. It was so-called BIM Level 1. However, even if you evolve to BIM Level 2 and use full potential of BIM you will still need to have CAD software installed. And probably you will always need to have installed CAD software along with your BIM software. Here you can see some advices regarding Revit and AutoCAD integration.
For concept design you don’t need to care about software and tool that you will use – use any tool that you prefer. You can use tracing paper, AutoCAD, SketchUp, and so on. Also at the concept stage you can use generative design tools as assistants in your design. When you reach an optimal design you can start your Revit model. Of course, if you created drawings in AutoCAD you will link these drawings as underlay and model Revit elements. The good practice is to not model Revit elements by picking lines from DWG underlay. Besides underlays, CAD files are commonly used for site plans and details in Revit.
- Link instead import. Imported CAD files can significantly increase size of your model and it’s harder to manage. In general, it’s better option to link CAD files except you have special reason.
- Use worksets. If you work in a workshared model, put all your CAD imports/links into one or several worksets. This way you can easily control it, quickly open your models without DWGs, and turn on/off that worksets anytime. Note that turning on/off worksets is not same as reloading files in these worksets.
- Share coordinates. You can share Revit coordinates to CAD files and link these files across multiple models of your Revit project using shared coordinates.
- Create and share a DWG/DXF Export Setup. Create export setup that you can use across projects. This setup can be exported with Transfer Project Standards (for more information see Revit tip #9). In the Setup you can map Revit model with AutoCAD drawing: categories to layers, line patterns to linetypes, fill patterns to hatch patterns, Revit fonts to fonts in DWG; set colors (allows use of colors specified in the Revit views); specify if you are using shared coordinates; important option “Export views on sheets and links as external references” (it’s usually preferable to uncheck this option so your views on sheets and links will be exported as blocks instead of separate Xrefs); AutoCAD file format version, etc.
- Site plans. CAD files are usually used in combination with Revit elements for making site plans. Toposurface in Revit is usually modeled inside property line, and for outside representation is used DWG drawing. So drawing is prepared in AutoCAD so the lines inside property line are deleted.
- Create drafting views. Import a view from AutoCAD program as a drafting view. At first create a new drafting view (View -> Drafting View), then import/link CAD detail. In drafting views you can import/link only with checked “Current View Only” option. When you create a callout, section or elevation view, you can reference it to the drafting view (check “Reference Other View” in the Modify ribbon before placing a view). You can create a library of CAD details for your drafting views in Revit projects.
The other workflow is to export empty sheet with titleblock from Revit as DWG, then create details in AutoCAD. - Use plugins. CAD Files Explorer for Revit is an advanced add-in to manage DWG imports/links in both your Revit models and families. Purge CAD and Master Purger for Revit are free add-ins to easily purge imported/linked CAD files. Enhanced DWG Exporter is a free add-in that improves the Revit’s built-in “DWG Export” function. Link Visibility Manager is a free add-in to quickly hide/unhide CAD links in the views where links are visible.
You can also use Dynamo scripts, for example for deleting of Line Patterns that were imported from DWG files, and for deleting of imported/linked CAD files.
