IFC Import and Export Setup

This blog entry will introduce you to the IFC Linking and Export capability we find in Revit. The dataset we will use will be the: RAC_Advanced_Sample_Project, found in the following location on your local hard drive: C:\Program Files\Autodesk\Revit 2015\Samples

To export to an IFC format, browse to the Application menu, Export, IFC.

 

Within the Export IFC command, you will be able to specify four export properties:

• Export the current view only
•  Should walls and columns be split by storey or not
• Should base quantities be exported or not
• Should Space Boundaries be included in the export

 When the IFC file is linked into a new project, you will notice a few oddities in the file. First of all, the topography in the OFC file shows primary contours, secondary contours, as well as the triangulation edges.

Secondly, some walls and furniture elements are missing in plan view, and there seems to be a disconnect between the curtain wall door and curtain wall to the bottom left of the image.

Let’s investigate why this happened, and how we can remedy it from happening again in future. Firstly, let us look at the additional data files that are created when the IFC Export command is executed. We will find an export log file and export shared parameters file. 

The export log file will show errors that happened during the export process, the Revit entities that were processed, as well as the IFC elements that were created during the export.

The export shared parameters file will provide a list of shared parameters that were created, the kind of shared parameters (text, number, integer, etc.), its visibility setting (1=ON, 0=OFF), and whether the shared parameter is modifiable by a user (1=YES, 0=NO)

Now, during the export process, Revit will use a pre-defined text file to understand which IFC Class Name, and IFC Type to assign to which Revit categories. The IFC Options command can be accessed from the Application Menu, Export, Options icon, IFC Options.

You will be able to access the exportlayers-ifc-IAI.txt file through Revit’s interface. Changes can be made either from within Revit to the IFC Options, or by accessing the text file by browsing to the C:\ProgramDATA\Autodesk\RVT 2015\ folder location.

 

One can create or modify your own IFC Export Layers text file, but make sure that you comply to the layer requirements as set out in the text file (Indicated by a hashtag)

 Similarly, one will also have IFC Import options. These options can be accessed from the Application Menu, Open, IFC Options.

You will enter your Import IFC Options command, where you can start assigning Revit categories and sub-categories to the various IFC Class Names, and IFC Class Types.

Both the Import and Export Options for IFC file formats can be saved to an external file, and loaded into an existing project (If it has not yet been added to the existing company template/s).