How to Import and Export IFC Files in BricsCAD BIM

Quick answer: IFC (Industry Foundation Classes) is a platform-neutral, open data model describing building and construction industry information, providing interoperability between different BIM software platforms. BricsCAD BIM supports both IFC2x3 and IFC4 for import and export, merging their property namespaces into a single IFC namespace behind the scenes, the same namespace covered on this hub’s BIM data structure and customizing BIM quantities pages. IFC covers parametric and non-parametric shapes, material definitions, file metadata, and property sets; exported properties become IfcPropertySet entries, including any user-defined property sets. Alignments and TIN Surfaces import and export with IFC4X1; entities using Redway materials get a colour resembling their material-by-layer colour; exporting a date to IFC4 uses YYYY-MM-DD for IfcDate, any other format exports as IfcLabel instead.

IFC2x3 vs IFC4

IFC4 is an advanced schema built on IFC2x3, extending it and overcoming several limitations: more parametric support, more efficient mesh handling, and improved texture and lighting settings, alongside a larger, more granular set of property sets. For IFC4, the old coordination view is replaced by two official Model View Definitions, the IFC4 Reference View and the IFC4 Design Transfer View. As noted above, differences between the schemas are handled in the background, with both merged into a single IFC namespace.

IFC Import and Export Settings

Stored in the configuration file set by IFCSETTINGSCONFIG, all available in the Settings dialog:

Manage import settings via the IFC Import Settings dialog, and export settings via the Export To IFC dialog.

Importing an IFC File

1. Type IMPORT; the Import file dialog opens.
2. Select the IFC format (*.ifc;*.ifczip) from Files of type and choose your IFC model.
3. Click Open; the IFC Import Settings dialog opens. IFC2x3, IFC4, IFC4x1, and IFC4x3 (4.3.2.0) files can all be imported, merged into a single IFC namespace, and imported data integrates directly with BricsCAD’s data structure, ready to work with immediately, including any custom property sets. Important: IFC4x1 isn’t an official version, and while importing it is supported, its code isn’t actively maintained, other IFC versions are recommended instead. You can also create custom property sets and properties directly in BricsCAD BIM and associate them with imported entities.
4. Optionally adjust the IFC Import Settings dialog.
5. Click Import.

Exporting an IFC File

1. Type IFCEXPORT and choose Entire model (or select specific entities first and press Enter to export only those). The IFC file name dialog opens.
2. Choose the IFC format under Save as type and name the file.
3. Click Save; the Export to IFC dialog opens.
4. Optionally adjust the export settings there.
5. Click Export; the model saves, ready to use in any IFC-certified application.

Importing an IFC Project as Xrefs

1. Type IMPORT; the Import file dialog opens.
2. Choose the IFC format and your file; the IFC Import Settings dialog opens.
3. Under Profile settings, tick Explode spatial structure to XRefs and click Import; the drawing opens with an Xref created for each floor of each building, an easy way to split a large file into smaller BricsCAD files.

Exporting a BIM Project with Xrefs

1. Use the Xref option of BIMCLASSIFY to classify your Xrefs as BIM XReference. Important: skip this step, and your Xrefs export as blocks instead of separate entities that are actually part of the Xref.
2. Launch IFCEXPORT and press Enter; the IFC file name dialog opens.
3. Choose the IFC format, name the file, and click Save; the Export to IFC dialog opens.
4. Tick Merge Spatial Location Structure for XRefs.
5. Click Export; every Xref element merges onto a single Site and Building in the result.

Working with IFC Properties

1. Open the BIM Properties dialog via Home > Classify > Spatial Locations > Properties on the ribbon, or type BIMPROPERTIES.
2. Choose IFC from the Namespace dropdown.
3. Search the properties list for what you want.
4. Set Visible to Yes to show that section in the Properties panel, or No to hide it.
5. Under Categories, select the IFC Classes you want it displayed for.
6. Click OK.
7. Select an object of an enabled type or category (an Energy Conversion Device, for example) and scroll the Properties panel to the newly enabled section.
8. Fill in the data.

IFC properties for spatial elements can be added the same way through the Properties panel.

Profiles in IFC Import

When importing profiles from an IFC file, either import the profile properties contained in the file directly, or let BricsCAD search the Project and Central Database for matching profiles based on geometry. Either way, the result assigns the correct Profile Standard, Profile Name, and Profile Size in the Properties panel.

Supported IFC Classes

These match the same categories available as classify options in BIMCLASSIFY.

Backward compatible with older BricsCAD versions: IfcWall, IfcBeam, IfcSlab, IfcStair, IfcStairFlight, IfcRamp, IfcRampFlight, IfcRailing, IfcCurtainWall, IfcRoof, IfcBuildingElement, IfcSite, IfcBIMXreference, IfcGridAxis, IfcGrid, IfcAnnotation, IfcWindow, IfcDoor, IfcCovering, IfcFurnishingElement, IfcOpening, IfcDistributionControlElement, IfcDistributionPort, IfcDistributionFlowElement, IfcDistributionChamberElement, IfcEnergyConversionDevice, IfcFlowFitting, IfcFlowController, IfcFlowMovingDevice, IfcFlowSegment, IfcFlowStorageDevice, IfcFlowTerminal, IfcFlowTreatmentDevice, IfcFlowConnectionPoint, IfcMember, IfcFooting, IfcPile, IfcReinforcingBar, IfcReinforcingMesh, IfcTendon, IfcTendonAnchor, IfcPlate, IfcDiscreteAccessory, IfcFastener, IfcMechanicalFastener, IfcSpace, IfcBuilding, IfcBuildingStorey, and IfcDate.

Not backward compatible with older BricsCAD versions: IfcBuildingElementPart, IfcBuildingElementProxy, IfcDistributionElement, IfcElectricDistributionPoint, IfcElectricalElement, IfcElementAssembly, IfcEquipmentElement, IfcProxy, IfcTransportElement, IfcVirtualElement, IfcActuator, IfcAirTerminal, IfcAirTerminalBox, IfcAir-To-AirHeatRecovery, IfcAlarm, IfcAudio-VisualAppliance, IfcBoiler, IfcBurner, IfcCableCarrierFitting, IfcCableCarrierSegment, IfcCableFitting, IfcCableSegment, IfcChiller, IfcChimney, IfcCivilElement, IfcCoil, IfcCommunicationsAppliance, IfcCompressor, IfcCondenser, IfcController, IfcCooledBeam, IfcCoolingTower, IfcDamper, IfcDuctFitting, IfcDuctSegment, IfcDuctSilencer, IfcElectricAppliance, IfcElectricDistributionBoard, IfcElectricFlowStorageDevice, IfcElectricGenerator, IfcElectricMotor, IfcElectricTimeControl, IfcEngine, IfcEvaporativeCooler, IfcEvaporator, IfcFan, IfcFilter, IfcFireSuppressionTerminal, IfcFlowInstrument, IfcFlowMeter, IfcFurniture, IfcGeographicElement, IfcHeatExchanger, IfcHumidifier, IfcInterceptor, IfcJunctionBox, IfcLamp, IfcLightFixture, IfcMedicalDevice, IfcMotorConnection, IfcOutlet, IfcPipeFitting, IfcPipeSegment, IfcProtectiveDevice, IfcProtectiveDeviceTrippingUnit, IfcPump, IfcSanitaryTerminal, IfcSensor, IfcShadingDevice, IfcSlabElementedCase, IfcSolarDevice, IfcSpaceHeater, IfcStackTerminal, IfcSwitchingDevice, IfcSystemFurnitureElement, IfcTank, IfcTransformer, IfcTubeBundle, IfcUnitaryControlElement, IfcUnitaryEquipment, IfcValve, IfcVibrationIsolator, IfcWallElementedCase, IfcWasteTerminal, IfcAlignment, and IfcReferent.

Exporting a Structural Analysis Model

BIMANALYTICALMODEL can export a line model of a structure to either CIS/2 or IFC, confirming the same two export formats covered on this hub’s analytical model page. Choose Export and exit at the Command line to open the filename and format dialog and pick your export type.

Import/Export Mapping Files

By default, every entity imports or exports according to a default mapping, but a plain text mapping file (referenced by the Import or Export Mapping path) can override this:

• No text mapping: default mapping applies to everything.
• Special mapping for one entity: for import, write the IFC class then the BricsCAD class, for example IfcWall BimDbColumn; for export, write the BricsCAD class then the IFC class, for example BimDbWall IfcColumn. Any entity not listed still uses the default mapping.
• Exclude an entity: write the entity followed by skip, for example IfcWall skip (import) or BimDbWall skip (export).
• Import or export only the listed entities: list them, then add * skip on its own line, the asterisk means “everything else.”
• Handle all unlisted entities with the same special mapping: write * followed by the target class, for example * BimDbWall (import) or * IfcWall (export).
• Fall back to default mapping for specific entities even when using an asterisk rule: write the entity followed by its own default class, or the word default, for example IfcWall BimDbWall or IfcWall default (import), BimDbBeam IfcBeam or BimDbBeam default (export).

Worked example, creating an export mapping file:

1. Start from a fully classified BricsCAD model (run BIMIFY first if it isn’t classified yet).
2. Decide what to exclude, in this case windows, doors, and spaces, so only the building’s core geometry exports (without a mapping file, everything exports using the default IFC class).
3. Open a new plain text file in an ASCII editor like Notepad.
4. Follow the syntax rules: separate the BricsCAD entity and IFC entity with a single Tab (not a space or multiple Tabs, lines using those are ignored), one command per line. Note that a wall with a composition attached exports as IfcWallStandardCase rather than plain IfcWall, and that special-mapping an entity changes its properties to match the new category’s defaults.
5. This example needs two rule categories: excluding windows, curtain walls, doors, and spaces (BimDbWindow skip, BimDbCurtainWall skip, BimDbDoor skip, BimDbSpace skip), and mapping walls that were mistakenly classified as beams back to walls on export (BimDbBeam IfcWall). The same result is also achievable by listing only the entities you want to keep, followed by * skip.
6. Save the file.
7. Open the BricsCAD file you want to export.
8. Set the mapping file path: either type SETTINGS, go to BIM > Import and Export > IFC > Export mapping file path, click the three dots, and select your file, or type IFCEXPORTMAPPINGPATH and paste the file’s path when prompted.
9. Type Export, or click the BricsCAD icon in the ribbon and choose Export.
10. Choose the IFC format and save the file.
11. Verify the result by opening it in an IFC viewer, or by re-importing it into BricsCAD without an import mapping file active.

The same mapping approach works for imports too, starting from a model already divided into distinct IFC elements with BIM information.

Exporting Geographic Location

For IFC2x3: the Use Geographic Location from GEO dialog setting, in the Spatial Locations Manager dialog’s Site > Geographic reference point section, chooses which source to use. If False, Longitude, Latitude, and Elevation export from the Spatial Locations Manager dialog as IfcSite, with no CRS exported. If True, they export from the Geographic Location dialog instead, along with a Coordinate Reference System, as IfcSite and IfcProjectedCRS.

For IFC4: if a CRS is defined in the Geographic Location dialog, the Spatial Locations Manager’s setting is ignored entirely, Longitude, Latitude, Elevation, True North direction, and CRS all export from the Geographic Location dialog as IfcMapConversion and IfcProjectedCRS. If no CRS is defined there, no IfcMapConversion or IfcProjectedCRS exports at all, and Longitude, Latitude, and Elevation export as IfcSite instead, following whichever source the Spatial Locations Manager’s setting points to.

Guidelines for Exporting Colors and Transparency

BricsCAD BIM tries to keep a model’s IFC-viewer appearance as close as possible to its BricsCAD appearance, though IFC format limitations mean colors and transparency don’t always export perfectly. One scenario worth avoiding specifically: within a single block, setting some solids to By Block color while assigning others a specific color directly, the By Block solids won’t get the block reference’s color assigned correctly in the export.

Frequently Asked Questions

Can I import IFC4x1 files reliably in BricsCAD? Importing them is supported, but IFC4x1 isn’t an official version and its code isn’t actively maintained, other IFC versions are recommended instead.

What happens to my Xrefs if I export without classifying them as BIM XReference first? They export as blocks instead of separate entities that are part of the Xref, classify them with the Xref option of BIMCLASSIFY first.

Where does BIMANALYTICALMODEL export a structural line model to? Either CIS/2 or IFC, confirming the two formats covered on this hub’s analytical model page.

What color scenario should I specifically avoid before exporting to IFC? Mixing By Block colored solids with specifically colored solids within the same block, the By Block solids won’t receive the correct block reference color in the export.