SMACNA Ductwork Modeling in Revit: Clearance & Flanges
Duct models that pass clash detection still trigger RFIs from the field. Installers find flanges pressed against beams, no room for bolting tools and joints that insulation cannot cover. They file an RFI and the schedule slips by days. The fabricator ends up doing rework. Most of these problems come from models built for design intent. Teams that adopt SMACNA standards in Revit HVAC workflows from the first layout catch problems early. That work starts with how the duct's drawn. Why Design-Intent Duct Models Fail on the Jobsite A generic Revit duct carries size, system type and flow direction. That is enough, for design review. However, a sheet metal shop drawing needs more. It must know how the duct cuts, how it seams and how it joins parts. Its real footprint has three layers: · Insulated body: Nominal duct plus wrap on every side. · Joint envelope: The flange or connector proje...