© 2010 Autodesk
Introduction to Revit 2011 API
DB Element
Element versus Symbol
§
§
Element
Symbol
Kind of Element in UI
Derived from Element/TypeOf
Category
 
Derived from Symbol/TypeOf
Category
Wall
HostObject/Wall
Walls
HostObjAttributes/WallType
Walls
Door
Instance/InsertableInstance/FamilyInstance
Doors
InsertableObject /FamilySymbol
Doors
Door Tag
IndependentTag
Door Tags
InsertableObject /FamilySymbol
Door Tags
Window
Instance/InsertableInstance/FamilyInstance
Windows
InsertableObject /FamilySymbol
Windows
WindowTag
IndependentTag
Window Tags
InsertableObject /FamilySymbol
Window Tags
Opening
Opening
Rectangular Straight  Wall Opening
< null >
  ---
Floor
HostObject/Floor
Floors
HostObjAttributes/FloorType
Floors
Ceiling
< Element >
Ceilings
HostObjAttributes
Ceilings
Roof
HostObject/RoofBase/FootPrintRoof,ExtrusionRoof
Roofs
HostObjAttributes/RoofType
Roofs
Column
Instance/InsertableInstance/FamilyInstance
Columns
InsertableObject /FamilySymbol
Columns
Component (Desk)
Instance/InsertableInstance/FamilyInstance
Furniture
InsertableObject /FamilySymbol
Furniture
Component (Tree)
Instance/InsertableInstance/FamilyInstance
Planting
InsertableObject /FamilySymbol
Planting
Stairs
< Element >
Stairs
< Symbol >
Staies
Railing
< Element >
Railings
< Symbol >
Railings
Room
Room
Rooms
< null >
  ---
Room Tag
RoomTag
Room Tags
< Symbol >
Room Tags
Grid
Grid
Grids
LineAndTextAttrSymbol/GridType
< null >
Lines
ModelCurve/ModelLine
Lines
< null >
  ---
Ref Plane
ReferencePlane
Reference Planes
< null >
  ---
Dimension
Dimension
Dimensions
DimensionType
< null >
Section
< Element >
Views
< Symbol >
< null >
Text
TextElement/TextNote
Text Notes
LineAndTextAttrSymbol/TextElementType/TextNoteType
< null >
Level
Level
Levels
LevelType
Levels
Model Group
Group
Model Group
GroupType
Model Groups
Create…/Walls
Instance/InsertableInstance/FamilyInstance
Walls
InsertableObject /FamilySymbol
Walls
The second table shows a similar list with the symbol type and its corresponding category added.  The two columns on the right show the type and category of the symbol or family type used for each model elmeent, represented by a family or dedicated type instance. It shows the correspondence between the instance and symbol elements. The symbol used for a wall is WallType, floor uses FloorType, roof uses RoofType.  For component families such as door, window, column, desk and tree, the symbol type is FamilySymbol.  Again, in these cases you need to rely on the category to tell the different family symbols apart, while there are designed types for system families.