# User Defined Properties

Besides the Common Property Sets defined in the IFC Schema, it is also possible to define custom property sets and Revit offers two ways to do this: using schedules or a configuration file. 

Note: only the official property sets defined in the IFC schema are allowed to start with “Pset\_ “

The following video provides an of the topics discussed in this section:\ <mark style="background-color:orange;">▶️</mark> [<mark style="background-color:orange;">Export any Revit Property to IFC using Custom Property Sets</mark> ](https://youtu.be/SswHKtcM3mI?si=lFgb2niTXjn_f8AV)


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