
What:
Easily export BIM data in Industry Foundation Classes (IFC) file format using Revit open-source IFC.
Who:
Architects, engineers, designers, project managers, BIM managers.
How:
Revit IFC export automatically exports IFC properties defined by buildingSMART data model standards as common property sets. However, almost every company has its own standard properties, which are not exported to IFC as standard settings. Export Custom BIM Data to IFC Using Schedules describes the workflow for using Revit schedules for defining custom property sets.
Another option for defining property sets outside a Revit project file is to use defined property sets in a text file. You can store these property sets in a network file accessible to everyone in the company:

The default property sets file is stored in this location (link valid for Revit 2018): C:\ProgramData\Autodesk\ApplicationPlugins\IFC2018.bundle\Contents\2018\DefaultUserDefinedParameterSets.txt
The default file is properly structured and has bracketed comments that guide you when you define your own property sets:

Here is an example of an edited file:

On the right, you can see the result of exporting a property set to IFC. You can then view it in Autodesk Navisworks.
You can add other property sets to the same file, or even define different property set files for different use cases.
Why:
Export your BIM Information to IFC.
What next?
For more information about Revit and IFC, see Export Custom BIM Data to IFC Using Schedules, Using Parameter Mapping Tables for IFC, and Exporting to Industry Foundation Classes.