The "Flood Area to create space" tool doesn't take into account the complete boundary of a room if there are some details in the room such as a slab offset. The "Flood Area to create space" tool will snap on every little detail or piece of other structures under or above the clip level.
When Flood Area to create space is selected there are options available that will allow you to create the space depending on scenario or situation:
- Note: The Display Unit for this setting can be changed. Go to the Preferences dialog, select the Building Architectural category, turn on the Unit of Display setting in the DataGroup Area Preferences group box, and enter the desired unit of display.