IFC Import and Export in BricsCAD – Bricsys Support and Help Center

Overview: In this lesson, you will learn how to import and export IFC files in BricsCAD BIM.

Lesson Objectives

After completing this lesson, you will be able to:

Import an IFC model to BricsCAD.
Export an IFC model from BricsCAD.
Use IFC properties.

Tutorial: How to import & export IFC files in BricsCAD BIM

About IFC

The Industry Foundation Classes (IFC) data model is designed to describe building and construction industry information. IFC is a platform-neutral, open-format file type. IFC provides interoperability between different BIM software platforms.

BricsCAD BIM supports IFC2x3 and IFC4 for import and export. It is certified for IFC 2X3 coordination view 2.0. The IFC standard includes both parametric and non-parametric shapes, material definitions, metadata in the BIM file, and property sets (PSets).

When you export an IFC file from BricsCAD, the properties will be exported as IfcPropertySet. These property sets contain common IFC properties. User-defined property sets can also be exported.

Mechanical system layouts, structural models, and architectural models that are exported from different IFC compliant software applications can be imported into BricsCAD BIM.

IFC2x3 vs IFC4

IFC4 is an advanced schema of IFC2x3. It is extended and overcomes certain limitations of IFC2x3. There are geometric and data improvements as well as new and changed Model View Definitions. Geometric improvements include more parametric support, more efficient handling of meshes and an improved way to add textures, lighting settings, etc. An increased number of property sets, make the IFC data model more complete and more granular. For IFC4 the coordination view has been replaced by two official Model View Definitions: the IFC4 reference view and the IFC4 Design Transfer View.

IFC import and export settings

The IFC import and export settings in the settings dialog:

Import Spaces	Enable/disable the import of IfcSpace entities as BIM Spaces. If enabled, IfcSpace entities will be imported as BIM Space entities. By default, this setting is enabled.
Import BIM Data	Enable/disable the import of BIM data from different BIM platforms to BricsCAD BIM. By default, this setting is enabled.
Import model position	Controls the insertion point of the imported model. The options are: 0: BricsCAD WCS matches the IFC Global Coordinate system. 1: BricsCAD WCS matches the IFC Site Location.
Import Parametric Components	Enables/disables the import of windows and doors as parametric components.
Import IFC project structure as xrefs	Enable/disable the import of IFC project structures as separate XRef drawings. If this setting is enabled, drawing files are created as XRefs. These files correspond to each building and each story of the IFC project structure.
Import BREP geometry as meshes	Enable/disable the import of BREP geometry as meshes. If this setting is enabled, BREPs in the drawing are converted into meshes. Enable this setting to prevent BricsCAD from converting all the geometry to solids. This decreases the import time of the model significantly.
Import IFC meshes as subdivision meshes	Enables the import of polyface meshes with no limitation of the number of faces.
Import mapping file path	Allows to specify an import mapping file path, see 'Import/Export mapping of IFC files'.
Export base quantities	Enables/disables exports derived from base quantities of BIM elements. If this setting is enabled, calculated quantities (e.g. length, thickness, height) for each BIM element will be exported to IFC.
Export elements on OFF and FROZEN layers	Enables/disables the export of BIM elements that are in Off and Frozen layers. By default, this setting is enabled.
Explode external references in IFC spatial structure	Enables/disables exploded external references in IFC spatial structures. If this setting is enabled, each external reference will be divided into the elements (e.g. IfcSite or IfcBuilding) based on the project spatial structure. Important note: use the BIM Classify command to Classify Xrefs as BIM XReferences prior to doing an export with this setting enabled. Otherwise, the result will be a block per Xref.
Tesselate complex curves and surfaces	Controls whether BSpline curves and surfaces are tesselated.
Always export swept solids as BRep	Allows to export all extrusions, revolutions, swept 3D solids with clippings and subtractions using a boundary representation (BRep).
Export mapping file path	Allows to specify an export mapping file path, see 'Import/Export mapping of IFC files'.
Export multi-ply elements as aggregated elements	Enables/disables the export of building elements with multi-ply compositions as aggregated entities. If this setting is enabled, each ply material belonging to a building element (e.g. wall or column) is calculated and exported individually.
Level of tessellation	Controls the level of tessellation of the exported geometry. If the 'Current' faceting option is chosen, the faceting as set by FacetRes or Modeler properties is used. Choosing the 'Low', 'Medium' or 'High' options of regeneration of the facets. This makes the process longer.
Export with unique guids	Defines whether a unique GUID for nested elements should be generated upon export. 1: unique guids for inside classified blocks, 2: inside classified Xrefs, 3: to enable both inside classified blocks and Xrefs.

Import an IFC file in BricsCAD

To import an IFC file into your project, type Import into the command line. The import file dialog box displays.
Select the .ifc file format (1) from the Files Of Type dropdown list and choose the IFC model you want to import.
Click Open to import the IFC model.

Note: Both IFC2x3 and IFC4 files can be imported. When the IFC file is imported the data from the imported file integrates with the BricsCAD data structure which means you can work with them right away. If the imported data contains custom properties, these property sets will be made available.
You have the ability to create custom property sets and properties directly in BricsCAD BIM and associate them with imported entities.
(Optional) Change the IFC import settings using the BIM section in the Settings dialog. See 'Change IFC import and export settings'.

Export an IFC file in BricsCAD

To export an IFC file in your project, click the BricsCAD icon and then select Export. The Export Drawing As dialog box displays.
Select the desired .ifc file format in the Save as type list and save the IFC model in a sensible location. You have the option between IFC2x3 (2) and IFC4 (3).
Click Save to export the IFC model.
The exported BIM model is saved as an IFC2X3 or IFC4 file and it is now ready to use in any IFC certified application.
(Optional) Change the IFC export settings using the BIM section in the Settings dialog. See 'Changing IFC import and export settings'.

Export an IFC file only for selected entities

To export IFC model partially in your project, type IFCEXPORT in the command line Or press the Export to IFC icon in the Home Toolbar.

You are prompted:
Select entities to export [Entire model/selection options (?)] <Entire model>:
Select the entities in your model space to export as IFC and press Enter.
The IFC file name dialog box displays:
Enter a name for the IFC file, choose the IFC format for export (IFC2x3 or IFC4) and click the Save button. The selected entities are exported to IFC.

Import an IFC Project as Xrefs

Go to Settings (type Settings in the command line or go to Settings in the ribbon > Settings).
Navigate to BIM > Import and Export > IFC.
Check 'Import IFC project structure as xrefs ' box (4).
Type Import into the command line. Specify which .ifc file you want to open and click Open.
The drawing will now open with Xrefs made for each floor in each building. This allows you to easily split large files into smaller BricsCAD files.

Export a BricsCAD BIM Project with Xrefs exploded

Use the BIM Classify command to Classify Xrefs as BIM XReferences.

Important note: If you don't go through this step, your Xrefs will be exported as blocks, instead of separate entities that are part of the Xref.
Go to Settings (type Settings in the command line or go to Settings in the ribbon > Settings).
Go to BIM > Import and Export > IFC.
Check 'Explode external references in IFC spatial structure' (5).
Click the BricsCAD icon and then select Export. Choose IFC2x3 or IFC4, specify the name of the exported drawing and click Save. The exported drawing will now have all Xref elements merged onto one Site and one Building.

Using IFC properties

In the ribbon go to Home > Database > Properties (6).
Select IFC2x3 in the Namespace dropdown-menu (7).
Search for the property you want to see in the properties list (8).
Set 'Visible' to 'Yes' for the section you want to see (9). Set to 'No' to hide a section.
In 'Categories' select the IFC Classes you wish to display (10).
Once all properties have been set, click OK.
Select an object of the type/category that you just enabled the Property Set for (i.e. in this example an Energy Conversion Device). Go to the Properties Panel. Scroll down to the Properties section you just enabled.
Fill in the data as required (11).

Note: IFC properties for spatial elements can also be added through the properties panel.

Profiles in IFC import

When importing profiles from an IFC file to BricsCAD, the profiles will be assigned with proper Profile Standard, Profile Name and Profile Size in the Properties Panel (12).

Supported IFC Classes

Following IFC Classes are supported by BricsCAD BIM. These are the same categories as the classify options in the BIMClassify command.

IfcWall
IfcBeam
IfcColumn
IfcSlab
IfcStair
IfcStairFlight
IfcRamp
IfcRampFlight
IfcRailing
IfcCurtainWall
IfcRoof
IfcBuildingElement
IfcSite
IfcGridAxis
IfcGrid
IfcAnnotation
IfcWindow
IfcDoor
IfcCovering
IfcFurnishingElement
IfcOpening
IfcDistributionControlElement
IfcDistributionPort
IfcDistributionFlowElement
IfcDistributionChamberElement
IfcEnergyConversionDevice
IfcFlowFitting
IfcFlowController
IfcFlowMovingDevice
IfcFlowSegment
IfcFlowStorageDevice
IfcFlowTerminal
IfcFlowTreatmentDevice
IfcMember
IfcFooting
IfcPile
IfcReinforcingBar
IfcReinforcingMesh
IfcTendon
IfcTendonAnchor
IfcPlate
IfcDiscreteAccessory
IfcFastener
IfcMechanicalFastener
IfcSpace

Exporting a structural analysis model

It is possible to export a line model of a structure using BimAnalyticalModel. It can either be exported to CIS/2 or to IFC. To set the export type, do one of the following.

Go to Settings. BIM > Import and Export > Structural Analysis Model > Export format and change the setting
Type AMExportFormat (1: IFC, 0: CIS/2)

For more information about this command, visit the Command Reference article BimAnalyticalModel.

For more information and examples, visit the Procedure article Analytical Model.

Import/Export Mapping of IFC files

When you Import/Export an IFC file in BricsCAD, all entities are imported/exported according to the default mapping. It is possible to import/export elements by special mapping and to exclude entities from import/export.

There are different txt configurations possible.

No text mapping
All entities will be imported/exported according to the default mapping.
Import/Export an entity by special mapping
In case of import, you first write the IFC class, followed by the BricsCAD class in which the entities should be imported. For example:
```
IfcWall BimDbColumn
```
In case of Export, you first write the BricsCAD class, followed by the IFC class in which the entities should be exported. For example:
```
BimDbWall IfcColumn
```
Note: when an IFC or BimDB entity isn't listed in the Import or Export mapping file, the default mapping will be used.
Exclude an entity from the Import/Export
Write the IFC or BimDb entity followed by 'skip'.

For example for Import:
```
IfcWall skip
```
For example for Export:
```
BimDbWall skip
```
Import/Export only the listed entities
List the entities that should be imported/exported followed by '* skip' on the next line. The asterisk refers to all not listed entities.
```
* skip
```

Import/Export all not listed entities by the same special mapping
Write the asterisk followed by the name of the class in which the entities should be imported.

For example for Import:
```
* BimDbWall
```
For example for Export:
```
* IfcWall
```
Import/Export entities by default mapping when using the asterisk
If you used one of the two previous options to skip all entities except the listed ones or to Import/Export by special mapping, you can still Import/Export entities by default mapping. Use the same text as you use to Import/Export an entity by special mapping. Instead of writing a special mapping next to the entity, write the default class or write 'default'.

For example for Import:
```
IfcWall BimDbWall
or
IfcWall default
```
For example for Export:
```
BimDbBeam IfcBeam
or
BimDbBeam default
```

Note: use the rules explained in 'Procedure: Export Mapping of IFC Files' to create an Import/Export Mapping file.

Procedure: Export Mapping of IFC Files

Start from a similar model in BricsCAD with all the building elements classified.

Note: If the elements are not classified, run Bimify to classify the model. For more information about this command, please read the command reference article Bimify.
The building consists of several building elements. Walls, slabs, doors, windows etc.

A custom Export Mapping file will be created to only export the geometry of the building without windows, doors or spaces.

Note: If you export the file without a mapping file, all the elements will be exported in the default IFC class.
Open a new txt file to create the export mapping file. Use an ASCII text editor, e.g. Notepad.
Follow these rules to add the text in the txt file according to 'Import/Export Mapping of IFC files':
- For export mapping, write the BimDb entity followed by the IFC entity. Separate the two words by a single Tab. Do not use a space or multiple Tabs to align the IFC classes. The lines with a space or multiple Tabs will not be used for Export Mapping.
- Only write one command per line.
- If a composition is attached to a wall in a BricsCAD file, the wall will be exported as IfcWallStandardCase instead of IfcWall.
  
  Note: When a building entity is imported/exported by special mapping, the properties of the element will change according to the default properties of the new category.
Two categories need to be added in the txt file to create the Export Mapping File for this model.
- Exclude windows, doors and spaces.
  The BricsCAD file contains normal windows and curtain walls, exclude both.
```
BimDbWindow skip
BimDbCurtainWall skip
BimDbDoor skip
BimDbSpace skip
```
- Export beams by special mapping.
  Some walls are classified as beams in the current BricsCAD file. These have to be exported as walls.
```
BimDbBeam IfcWall
```
- The resulting file looks like this:
```
BimDbWindow skip
BimDbCurtainWall skip
BimDbDoor skip
BimDbSpace skip
BimDbBeam IfcWall
```
  Note: you can also create a file where you include the entities you want to export, followed by '* skip'. This will give the same result.
Save the file to your computer.
Go to the BricsCAD file you want to Export.
Go through one of the following steps.
- Type Settings in the commandline and press Enter. Go to BIM > Import and Export > IFC > Export mapping file path. Click on the three dots and select the mapping file on your computer.
- Type IFCExportMappingPath in the commandline.
  You are prompted: New value for IFCEXPORTMAPPINGPATH <"">:
  Copy the path of the destination file in the commandline and press Enter.
Type Export in the commandline and press Enter or click the BricsCAD icon in the ribbon and select Export to export the file.
Select the desired .ifc file format in the Save as type list and save the IFC model to your computer.
To check if the IFC file is correct you can open the file in an IFC viewer or you can import the file in BricsCAD without an Import Mapping file. Type Import in the commandline, Press enter, select the file on your computer and click Open.

Note: The same workflow can be used to use Import Mapping of IFC Files. To use the import mapping, the model should contain BIM information. Start from a model that is divided into different IFC elements.