Just select the grid line of a ceiling, rather than the edge. Quote below:
…in Revit 2012! If you select just a grid line of a ceiling, you now get the option to Edit Boundary…
via
Revit ArchCenter: New Ceiling Modify Option
What Revit Wants
Just select the grid line of a ceiling, rather than the edge. Quote below:
…in Revit 2012! If you select just a grid line of a ceiling, you now get the option to Edit Boundary…
via
Revit ArchCenter: New Ceiling Modify Option