RFA File Support
The RFA file extension is associated with Autodesk Revit Architecture. A Revit model is based on a compilation of items called families. An RFA file contains such finished family data and is inserted similar to a cell (or block).
The RFA model can be placed as a parametric cell from the Cell Library dialog. When you place an RFA file as a parametric cell, the properties in the RFA file are populated in the Item Types dialog. The family types in the RFA file are populated as variations in Variables dialog. The parameters in the RFA file are displayed as variables and formulas are displayed as expressions in the Variables dialog. The parametric cell placed using RFA file works same as the parametric cell placed using .dgn or .cel file.
When you import or attach an RFA file, the properties from the RFA file are not displayed in the Item Types dialog.
When you import an rfa file into a dgn file, you can use the RFA Import Options dialog to import either as rfa cell in the active design model or as a SmartSolid.