Normal of the planar face.
Namespace: Autodesk.Revit.DBAssembly: RevitAPI (in RevitAPI.dll) Version: 23.0.0.0 (23.1.0.0)
Syntax
Remarks
This property is the "face normal" vector, and thus should return a vector consistently pointing out of
the solid that this face is a boundary for (if it is a part of a solid).