Missing Revit Properties

Occasionally, users find that their Revit properties (Identity Data, Constraints, Other, etc) are missing in their exported IFCs when opened in SMC.   The reason most often is that the IFC2X3 Coordination View 2.0 export setup was used in the IFC Export. By default, the IFC2x3 Coordination View 2.0 setup does not export internal Revit property sets.  Therefore, if you want these properties in your IFC, you’ll need to modify the setup and mark the Export Revit Property Sets check box in the Export Property Sets tab of the IFC Export dialog.

Also, IFC2X3 Coordination View 2.0 does not export Space boundaries.

In SMC, components such as walls, doors, floors, etc. that bind a room normally have a Referencing relation to a space.  This can be useful for instance in a check that every room has at least one door to enter/exit from.  In the IFC Export dialog in Revit, with the Space boundaries drop down set to none, these referencing relations are not included in the resulting IFC. Therefore, if you want these relations, you’ll need to modify the IFC2X3 Coordination View 2.0 setup and set the Space boundaries drop-down box to either 1st Level or 2nd Level in the General tab of the IFC Export dialog.

Alternatively, you can use the IFC2x3 Coordination View* setup, which exports Revit property sets and has Space Boundaries set to Level 1 as its default setting.

More information on exporting to IFC from Revit can be found in the article Exporting an IFC File from Revit to SMC

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Missing Revit Properties

Exporting an IFC file from Revit to SMC

If you are using Revit as your BIM Authoring Tool (BAT), in order to get the most out of your checks in Solibri Model Checker (SMC), you’ll want to ensure that the export of your Model to IFC is going to produce a quality file.  The following article provides some explanations, links to documentation, and suggestions for use with SMC.

Install the latest IFC exporter for Revit

The IFC Exporter For Revit updates the out-of-the-box IFC Exporter that comes with Revit. These later versions of the exporter have additional options, export functionality, and bug fixes, so it always recommended to keep up with the latest release. There are two locations where you can find the IFC Exporter for your version of Revit:

Sourceforge.net: http://sourceforge.net/projects/ifcexporter
Autodesk Exchange | Apps: https://apps.exchange.autodesk.com

IFC Mappings

The IFC Export Classes dialog in Revit allows a user to map a Revit Family Category to an IFC Class.  Elements within the model that are of a specific Family Category export to the corresponding IFC Class entered in the IFC Class Name box.  Alternatively, you can enter Not Exported in the box to ignore specific categories during export. To open this dialog in Revit, click File > Export > Options > IFC Options.

IFC Export Classes
IFC Export Classes

An important topic to touch on here is the export of IfcSpaces.  In order to run spatial analysis checks within SMC, you’ll want to ensure that the Rooms category is mapped to IfcSpace.  In addition, if you wish to use space grouping in SMC, for example to group spaces by Gross Area or Rentable Area, then the Areas category should be mapped to IfcSpace as well.  Lastly, if your Revit model contains MEP spaces that need to be checked in SMC, map the Spaces category to IfcSpace as well.  These mappings to IfcSpace stated above are the defaults of the AIA standard, which can be loaded by clicking the Standard button.

However, one mapping that isn’t part of the AIA standard is the mapping of the Grids category to the IfcGrid class.  In order for grids to display in the footprints of a model loaded in SMC, you’ll need to add this mapping.  More information on Grids in SMC can be found here: Grids in SMC and SMV

More information on the IFC Export Classes dialog can be found here: Load and Modify an IFC Mapping File

Information on how you can map to IFC classes within Revit families using the IfcExportAs and IfcExportType shared parameters can be found here: Specify IFC Entities for Families

IFC Export Dialog

Depending on whether or not you have installed the IFC Exporter for Revit, the IFC Export dialog will have either a simple out-of-the-box user interface with limited options or an updated user interface with many additional options that can be saved as setup configurations. In either case, to export to an IFC, click File > Export > IFC to open the IFC Export dialog.

The Out-Of-The-Box IFC Export Dialog

The out-of-the-box IFC Export dialog seen below has 5 settings options.  The most important is the Files of type dropdown, which specifies the format of the IFC export.   SMC supports all 5 formats; however, in most cases, IFC 2×3 can be selected, which is the default version that has been certified for export in Revit.

Out-of-the-Box IFC Export Dialog
Out-of-the-Box IFC Export Dialog

Of the three checkbox options, you should leave Current view only unchecked so the entire project is exported.  With the option marked, if you export from a 3D View which doesn’t allow the display of rooms, space will be missing in the resulting IFC export.  In many cases, the Split walls and columns by story checkbox should be checked so the walls and columns are divided by the floor they are on.  This often comes in handy for dimensions and counts in Information Takeoff (ITO) within SMC, or pinpointing issues with locations of walls and columns when running checks. Export base quantities can be marked for additional property information that can be used in rule checks or ITO reporting.

More information on these settings can be found here: Export a Project to IFC

IFC Exporter for Revit Alternate UI Dialog

If you’ve installed the IFC Exporter for Revit, the IFC Export Dialog is updated with additional options with the ability to store these options as setup configurations.  The IFC Export dialog comes with 9 setup configurations, which are shown below:

IFC Export Dialog
IFC Export Dialog

The following tables outline the different options between the 9 setup configurations.  This first table lists the setup configurations that use the IFC2x3 scheme. As with the out-of-the-box IFC Export dialog, in most cases you should use the IFC2x3 Coordination View setup. As seen in the table below, this setup does not split walls and columns by level.  Therefore, before you export, you should duplicate the IFC2x3 Coordination View setup, which thereby allows you to modify the options to mark the Split walls and columns by level option.

Setup/File Version IFC2x3 Coordination View 2.0 IFC2x3 Coordination View IFC2x3 GSA Concept Design BIM 2010 IFC2x3 Basic FM Handover View IFC2x3 Extended FM Handover View
File Type IFC IFC IFC IFC IFC
Space Boundaries None 1st Level 2nd Level 1st Level 1st Level
Phase to Export Default Phase to export Default Phase to export Default Phase to export Default Phase to export Default Phase to export
Property Sets IFC Common Only Internal Revit, IFC Common Internal Revit, IFC Common IFC Common Only IFC Common, Schedules, User-defined
User-defined Property Sets X
Base Quantities X X X
2D Plan View Elements X X X X
Bounding Box X X
Solid Models When Possible X X
Use Coarse Tessellation for Some Breps X X X X X
Split Walls and Columns X

SMC does support IFC2x3 Coordination View 2.0 and has received the IFC Coordination View 2.0 Import Certification (Click Here).  If you wish to use this setup configuration from Revit, as with the IFC2x3 Coordination View setup configuration, it is recommended that you mark the Split walls and columns by level option.  However, the IFC2x3 Coordination View 2.0 setup does not export internal Revit property sets (e.g Identity Data, Data, Other, etc.). Therefore, you should also mark the Export Revit Property Sets checkbox in the Export Property Sets tab of the IFC Export dialog.

The following table outlines the differences between the setup configurations that use the older IFC2x3 scheme:

Setup/File Version IFC2x2 Coordination View IFC2x2 Singapore BCA e-Plan Check
File Type IFC IFC
Space Boundaries 1st Level 1st Level
Phase to Export Default Phase to export Default Phase to export
Property Sets Internal Revit, IFC Common Internal Revit, IFC Common
User-defined Property Sets
Base Quantities
2D Plan View Elements
Bounding Box
Solid Models When Possible
Use Coarse Tessellation for Some Breps X X
Split Walls and Columns X

The following table outlines the differences between the setup configurations that use the latest IFC4 specification.

NOTE: SMC does not currently support IFC4 files.

Setup/File Version IFC4 Basic Coordination View 2.0 IFC4 Reference View
File Type IFC IFC
Space Boundaries None None
Phase to Export Default Phase to export Default Phase to export
Property Sets IFC Common Only IFC Common Only
User-defined Property Sets
Base Quantities
2D Plan View Elements
Bounding Box
Solid Models When Possible
Use Coarse Tessellation for Some Breps X X
Split Walls and Columns
Exporting an IFC file from Revit to SMC