Use the classification file to assign classification numbers to families. The classification numbers organize the families into groups used during the construction process or may be used to classify elements in your model in other ways.
The classification table that ships with Revit LT is a sample file. Edit the sample file, or replace it with one using your own classification system.
Edit the classification file
The classification number file is a tab delimited file. Values in the file are separated by tabs, each line of the file represents an entry in the table.