The Floor List command is used to create and modify floors in the project.
To modify the list of floors, go to
Ribbon: DM Electrical->Buildings and Rooms-> 
Floor List
Pulldown Menu: DM Electrical->Building Definition->Floor List
Floor Information Dialog Box
See the Common Schedule Dialog Box Features section for more information about how this dialog box works. This section describes the Rename, Find, Previous, Next, New, Copy, Save, and Delete buttons.
Default Ceiling Height: The default height of the ceiling for rooms on this floor. The ceiling height is used to determine the room cavity ratio and mounting height for indoor photometrics. This value can be overridden for individual rooms. See the Distance Input Format section for more information about specifying this height.