Assign a subcategory to a reference plane to control visibility and graphics settings.
Adding a Subcategory to a Reference Plane
Use the subcategories to create different line colors and line styles for reference planes so that it is easy to distinguish how a reference plane is used in Revit LT families and in complex views and models.
To create a reference plane subcategory
As an alternative, you can create a subcategory from the Properties palette when a reference plane is selected. Under Identity Data, for Subcategory, click the drop-list and click <Create New Subcategory>.