Click Architecture tab Build panel (Mullion). Highlight the grid line to which to add the mullions, and click to select it. Tip: Hold Shift to place a mullion only on the selected segment. Or hold Ctrl to place mullions on all open grid segments.
Click Architecture tab Build panel (Mullion). Highlight the grid line to which to add the mullions, and click to select it. Tip: Hold Shift to place a mullion only on the selected segment. Or hold Ctrl to place mullions on all open grid segments.