Nvisworks Splitting Geometry into Surfaces

[civicduty]

Hey everyone. I am new here so please be gentle to the noobie. I am doing clash detection for the first time using Navisworks 2012. I am noticing that Navisworks is breaking apart the geometry into surfaces instead of solids (see attached). Is this normal? Did I miss a check box somewhere?

The process: Architectural and Structural models are done in their respective Revit platforms. The structural is linked into the architectural. I exported the architectural model and the linked structural model together because the structural engineer did not use the shared coordinates.

Any help or insight would be much appreciated.

Thanks,

Jason