The first step in setting up a landscape/site in Revit, is linking in the CAD survey. While it is easy to do, there are a few settings that you want to make sure you have right (especially if you have CAD files pre-linked in your project template).
I’ve highlighted the important settings below. The rest don’t matter as much, or are personal preference (I prefer to preserve my colors). Import units usually auto-detects correctly, but occasionally it doesn’t (so watch out for that).
Current view only and correct lines that are slightly off axis should always be unchecked. Layers/Levels should be set to All. [Update] For Positioning, either Auto – Center to Center or Origin to Origin will work, though Origin to Origin is usually the safest option. I recommend against all of the Manual options, as discussed in a later post: Linking CAD Files with Large Extents.
It is also best practice to put dwg links on a separate workset (one that is not visible in all views). That way they only show up in plan (and not sections and 3D views).
Once it is linked in correctly, pin it down and be sure to Establish Coordinates via the Survey Point.
Managing linked CAD layers can become tedious, especially if you have your import settings tied into view templates. It is easiest to use query/hide in view to turn off large sets of layers and then tie those settings back into your view template periodically, as needed. This saves time in trying to navigate through long list of layers.
Additional Notes:
- Typical utility CAD linetypes (those with letters) do not translate into Revit at all. period. Only the line will show up. (a generic annotation can be used if you still want to have that letter… don’t use text)
- Any layers that are added to the dwg will pop-up (rather annoyingly) as they are created. (This is the main reason I preserve colors, to monitor new layers more easily)
- Nested Attached Xrefs will show up in the CAD link. (Overlay Xrefs seem to be temperamental, showing up often, but not always. I’ve found the only way to ensure they don’t show through is to unload them.)
- Keep your CAD extents below 20 miles. If the extents of the CAD file are larger than 20 miles, you will get the following error every time you reload the dwg/ open your project file (this error also happens while opening any Revit file that has your file linked in. So architects, if you’re seeing this error in reference to any site/civil/landscape dwgs, feel free to ask us to clean up our CAD file. It does get annoying and under most circumstances, shouldn’t be happening.)