In Revit, you use the Pipe Sizing dialog to specify the method used to automatically size or calculate sections of pipe using friction and/or velocity sizing methods.
Topics in this section
Fixture Units to Flow (GPM) Conversion Revit performs a general conversion from fixture units to flow, using the values found in the 2006 International Plumbing Code (IPC), Table E103.3 (3).
About Pressure Drop Calculation Revit computes pressure losses in piping based on the geometry and roughness of piping, fluid density, and fluid dynamic viscosity.