You can add an end cap to the open end of duct and pipe content.
Revit uses the information specified in the routing preferences to determine which type of end cap to add.
To add a cap to duct or pipe
Caps are added to all open ends of the selected element.
To add a cap to a selected duct or pipe connector
To add a cap to a pipe or duct network
Click Modify|Ducts tab or Modify|Pipes tabEdit panel Cap Open Ends.
Caps are added to all open ends of the selected content.
The new caps are highlighted and a warning dialog displays the number of caps that were added. Use the dialog to remove caps or display details about where caps were added.