For a multi-level Roof, select the line indicating the Roof level, then use pet palette commands to edit the vertical position or geometry of the Roof level.
Edit Level Height
Drag Level Horizontally
Choose the Drag Level Horizontally command from the pet palette to move the level horizontally.
If you drag the level all the way to the edge of the Roof, that edge is gabled:
Relevant topics
Reference Levels Preferences
You can define optional Reference Levels that will help you position elements. This is done at Levels Preferences (Options > Project ...
Split Levels – Tips&Tricks
Overview of the Split Levels in ARCHICAD - Types, Design Process, Dilemmas and their Solution
Stories/Levels
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Set up the ARCHICAD stories.
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