The surface type subcategory element id associated with the ConceptualConstructionType. 
   Namespace:   Autodesk.Revit.DB.Analysis  
  Assembly:   RevitAPI  (in RevitAPI.dll) Version: 2015.0.0.0 (2015.0.0.0) 
  Since:  2012 
  Namespace:   Autodesk.Revit.DB.Analysis  
  Assembly:   RevitAPI  (in RevitAPI.dll) Version: 2015.0.0.0 (2015.0.0.0) 
  Since:  2012