Get interior edges of fascias

Hello all.

Is it possible to get only the upper interior edge of an element?
I need to get the edges of the roof fascia that connect with the perimeter of the roof.

Yes, there are several ways to do this, mostly boiling down to basic geometry querries. What have you tried so far? Some ideas:

  • Projecting the roof onto the top surface of the parapet wall.
  • Getting the perimeter curves of the top face of the parapet wall and finding the interior curve (the one with less area).
  • Pulling all parapet and roof curves onto a common plane and finding which have a distance of 0 to the roof.