IFC Export Guidelines in Revit

Owned by Gwen Guerrero
28 Oct, 2022
3 min read

Revit exports building elements to an IFC file based on the categories (and subcategories) to which the elements belong.

While most IFC Types are mapped by default, elements like elevators and escalators are usually not. Basically, any complex element that is usually modeled under Generic Models are likely to not have a direct mapping from Revit to IFC. This documents show how to map a Revit family to an IFC type. We will be mapping elevators

A typical elevator might be modeled under Generic Models in Revit.

To map a family to an IFC entity

  1. Create shared parameters named IFCExportAs and IFCExportType.
    Save these shared parameters to a file that resides in a network location, so that you can add the parameters to other families and projects.
    For example, in a folder where you store other corporate standard files, create a parameter file named IFCexportParameters.txt (or anything reasonable). You only need to create these shared parameters once. You can reuse them in multiple families.

  2. Use the Family Editor to create a new family or to modify an existing family. Open Revit and locate the elevator family element

  3. Add the shared parameters to the family:

    1. In the Family Editor, click Create tab Properties panel (Family Types).

    2. In the Family Types dialog, for Name, select a family type.

    3. Under Parameters, click Add.

    4. In the Parameter Properties dialog, under Parameter Type, click Shared parameter, and click Select.

    5. Navigate to the shared parameters file that defines IFCExportAs and IFCExportType (for example, IFCexportParameters.txt), and open the file.
      Note: You can use this dialogue to create the parameters that do not exist

    6. In the Shared Parameters dialog, under Parameters, select IFCExportAs, and click OK.

    7. In the Parameter Properties dialog, under Parameter Data, for Group parameter under, select IFC Parameters.

    8. Make sure that Type is selected, and click OK.

      In the Family Types dialog, IFCExportAs displays in the parameter list.

    9. Under Parameters, click Add.

    10. In the Parameter Properties dialog, under Parameter Type, click Shared parameter, and click Select.

    11. In the Shared Parameters dialog, under Parameters, select IFCExportType, and click OK.

    12. In the Parameter Properties dialog, under Parameter Data, for Group parameter under, select IFC Parameters.

    13. Make sure that Type is selected, and click OK.

      In the Family Types dialog, IFCExportType appears in the parameter list.

    14. Specify values for IFCExportAs and IFCExportType. You might have to reload the Family before the parameters will be visible

      When you add the shared parameters to one family type, Revit LT automatically adds them to all types in that family. Next, you can specify values for each parameter in each family type.

      1. In the Family Types dialog:

        • For Name, select a family type.

        • For IFCExportAs, specify the desired IFC class.

        • For IFCExportType, specify the desired IFC type.

        • Click Apply.

Now when you export your project to IFC, the families will be mapped to the correct IFC class type.

Source: https://knowledge.autodesk.com/support/revit-lt/learn-explore/caas/CloudHelp/cloudhelp/2019/ENU/RevitLT-DocumentPresent/files/GUID-7119A8C3-A0EE-4568-8C35-750410D867C9-htm.html