Identifying Elements
In Revit, the easiest way to judge whether an element is a FamilyInstance or not is by using the properties dialog box.
- If the family name starts with System Family and the Load button is disabled, it belongs to System Family.
Figure 41: System Family
- A general FamilyInstance, which belongs to the Component Family, does not start with System Family.
- For example, in the following picture the family name for the desk furniture is Desk. In addition, the Load button is enabled.
Figure 42: Component Family
- There are some exceptions, for example: Mass and in-place member. The Family and Type fields are blank.
Figure 43: Mass or in-place member example
Families in the Revit Platform API are represented by three objects:
- Family
- FamilySymbol
- FamilyInstance
Each object plays a significant role in the family structure.
The Family object represents an entire family such as Single-Flush doors. For example, the Single-Flush door Family corresponds to the Single-Flush.rfa file. The Family object contains several FamilySymbols that are used to get all family symbols to facilitate swapping instances from one symbol to another.
The FamilySymbol object represents a specific set of family settings corresponding to a Type in the Revit UI, such as 34"×80".
The FamilyInstance object represents an actual Type (FamilySymbol) instance in the Revit project. For example, in the following picture, the FamilyInstance is a single door in the project.
- Each FamilyInstance has one FamilySymbol. The door is an instance of a 34"×80".
- Each FamilySymbol belongs to one Family. The 34"×80" symbol belongs to a Single-Flush family.
- Each Family contains one or more FamilySymbols. The Single-Flush family contains a 34"×80" symbol, a 34"×84" symbol, a 36"×84" and so on.