The information in this article applies to:
I see perpendicular lines on certain edges of my roof planes. What are these lines, and how do I hide them?
What you may be seeing on your roof planes are roof baseline indicators. A roof baseline is the uppermost portion of a roof plane directly above the main layer of a wall. A roof section's baseline is the line in 3D space around which the roof section pivots as you alter the roof section's pitch. The baseline may also be drawn over a CAD line or at the corner or edge of an existing roof section.
If, for example, you were looking at a truss or rafter, the baseline would be on the top of the rafter or truss. The baseline would be located at the point where the truss or rafter sits directly above the main layer of the wall the roof plane is resting on.
Alternatively, you can change the Color, Line Weight, and Line Style of this layer to more easily distinguish your roof baselines from other architectural objects and CAD lines in your drawing.