A curtain walls can be reoriented to facing inside
the building or outside the building.
Flip tool
toggles the curtain wall facing inwards / outwards.
For existing curtain wall in the view, select the corner edit
handle.
The mini toolbar opens.
Select the
(Flip)
tool.
The selected curtain wall flips the
orientation.
Alternatively, you can simply select the curtain wall and
then select
(Flip)
tool from the
Modification > Modify
Selected > Modify Curtain Wall
ribbon.