A main model can federate other models: structure, plumbing, HVAC, electrical… Each trade remains a separate file, overlaid in the same coordinate system.
To add an external link, open the main model's menu in the folder tree and choose “Add an external link”, then drop the file (.rvt, .ifc or .nwd). It is converted like a regular model, then appears under “External links” in the main model's tree.
In the viewer, each external link is turned on or off with one click in this list: you can show a single trade, or overlay them to check for clashes. Observations placed on an object of an external link are attached to that object and remain visible whatever the display.
Deleting an external link (link menu, “Delete”) removes it from the main model without affecting the original file in the CDE.
