In Revit 2013, you can't tag the slope of ramps in Plan views using the Spot Slope tool. There are workarounds out there already, but here is an easy one:

  1. Make a new Generic Model Adaptive family with 2 Placement Points
  2. Make a spline between these two points (select them and then hit the spline by points button). Set its category to Invisible
  3. Load this Family into a Project, and using a 3D view, place it at the centre line of a ramp (the two points should snap to the correct location in 3D)
  4. In a Plan view, use the standard Spot Slope tool in Revit - just pick the adaptive component "line" that you just placed.

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