I am using an import a RIF file from revit. The duct in revit has been enlarged and has the liner in it. When I bring the duct in Fabrication CADMEP the duct is the right size but does not have the liner. Is there a way for the service to add the liner. The other problem is when I add the liner manually it is enlarging the duct again making the duct 2" larger than it should be. I have a 14" x 14" with a liner so the duct opening is 12" x 12" but when I add the liner it is making the duct 16" x 16" with a opening of 14" x 14" which I do not want. I want the size to remain the same that is being imported in from Revit RIF file.

Is there a way to add liner without the duct increasing in size?

Appreciate your help,

Ken