Use the following settings on the Properties palette while drawing duct.
Video: Duct Options Bar Settings
- Level: (3D, elevation, and section views only) specifies the reference level for the duct.
- Width: specifies the width for a rectangular or oval duct.
- Height: specifies the height for a rectangular or oval duct.
- Diameter: specifies the diameter for a round duct section.
- Middle Elevation: Specifies the vertical elevation of the duct relative to the current level. You can enter a middle elevation value or select from a list of remembered middle elevation values.