Curtain panel normals

I am trying to quantify the direction of total exterior glazing. The goal is to produce a Revit schedule as shown in the attached graphic. I have been successful in getting normals for each curtain panel, then comparing them with the X axis vector to get the direction of each panel.

 

 

 

 

 

 

 

X axis being the East direction. The problem is this:

The normals sometimes face the exterior (as desired), but sometimes face the interior, which is incorrect. Any suggestions of how to control the Exterior / Interior of curtain panels?

Glazing Orientation Schedule

 

 

 

 

 

 

 

 

Glazing Orientation

I am a little surprised to see no one knows how to control the Normals of a geometry. I would think that ability is critical for numerous variety of analysis.

I would appreciate any feedback, including a completely new direction for accomplishing my end goal as described above.

 

Thanks!

 

How did you get the panel normals?

By drawing perimeter polylines for all panels, surface by patch, then normal through point. I couldn’t use “CurtainPanel.PanelPlane” node because it was it was dropping some panels.