I am new to 3D modelling and Part Builder in Civil 3D, but I believe for very complex objects, such as valve chambers that contain various intricate details, it will be much easier to model in the 3D work space than the Part Builder.
As such, can I create a 3D solid in the AutoCAD 3D modelling environment and later on add the necessary descriptive parameters inside the Part Builder environment. Alternatively, can I import an IFC file into Part Builder?