Bring a DWG into Revit

Why linking rather than importing

An imported CAD file is copied into the Revit project permanently. Every line, every layer, every text style and every block definition becomes part of your file. If the drawing is updated, you delete the old import and do it again — and the line styles and layers it created stay behind.

A linked CAD file stays an external file. Revit references it, shows it, and updates it when the original changes — Manage, Manage Links, Reload. Remove the link and everything it brought with it goes too.

The practical consequence is file bloat and style pollution. A project with a few imported DWGs accumulates hundreds of line styles and layers that cannot be purged cleanly, and the file grows. This is the single most common piece of advice experienced Revit users give, and it is worth following: link, do not import.

The exception is small, one-off geometry you genuinely want to become part of the project — a detail component profile, a logo for a title block. Even then, importing into a family rather than into the project keeps the mess contained.

Using the drawing once it is in

The usual reason for bringing a DWG into Revit is to trace over it: a survey, an existing-conditions plan, a consultant’s layout. The linked drawing sits underneath and you model on top of it using Revit elements, which is the whole point — you want walls that know they are walls, not lines.

Revit can snap to the linked geometry, which makes tracing quick. It cannot convert the lines into walls automatically, and any tool that claims to do so produces results that need more correcting than starting fresh would have taken.

For a survey drawn at real-world coordinates, use Shared Coordinates rather than Origin to Origin: Manage, Coordinates, Acquire Coordinates, then pick the link. That tells Revit where the building sits in the world without moving your model a kilometre from its own origin, which causes accuracy problems in Revit.

If the DWG will not come in properly

The most common failures are scale and position. Scale is the import units setting — set it explicitly rather than trusting Auto-Detect if the result looks wrong. Position is usually a drawing whose geometry sits far from its origin, which Origin to Origin faithfully reproduces.

A drawing with a great deal of unnecessary content — hatching, dozens of layers, external references of its own — is worth cleaning in AutoCAD before linking. PURGE and AUDIT, then save a copy with only the layers you need.

If the file is a DXF rather than a DWG, Revit links it the same way through Insert, Link CAD. DXF is the published format and generally imports more predictably.