IFC 4.3.0.1 (IFC4X3_TC1)

4.6.1 Object Typing

Object occurrences can be defined by a particular object type, using the Object Typing concept. A pair of entities are defined for most semantic objects - an object occurrence entity and a corresponding object type entity.

On instance level, an object occurrence instance may have:

  • similar state as its object type instance by applying all characteristics defined at the type;
  • overridden state for particular characteristics;
  • no defined object type instance.

Characteristics defined at the object type level may include:

  • common naming and predefined type;
  • common properties within a type driven property set;
  • common geometry representations, applied as mapped representation to each occurrences;
  • common material assignments (with exception of material set usages);
  • common definition of a decomposition structure.

Many object occurrence and object type entities have an attribute named PredefinedType consisting of a specific enumeration. Such predefined type essentially provides another level of inheritance to further differentiate objects without the need for additional entities. Predefined types are not just informational; various rules apply such as applicable property sets, part composition, and distribution ports. If the object is typed by an IfcTypeObject, then the PredefinedType at the IfcObject occurrence shall only be used if the PredefinedType at IfcTypeObject is set to NOTDEFINED.

The following diagram shows the generic classes and relationships used when applying this concept. In addition, concepts may have particular importance to common or standardised industry practices and scenarios. For these specific usage scenarios, the tables below shows a recommended list of general usage patterns that users may adopt.

G IfcObject IfcObject 1. GlobalId [1:1] 2. OwnerHistory [0:1] 3. Name [0:1] 4. Description [0:1]      HasAssignments [0:?]      Nests [0:1]      IsNestedBy [0:?]      HasContext [0:1]      IsDecomposedBy [0:?]      Decomposes [0:1]      HasAssociations [0:?] 5. ObjectType [0:1]      IsDeclaredBy [0:1]      Declares [0:?] HasType      IsTypedBy [0:1]      IsDefinedBy [0:?] IfcRelDefinesByType IfcRelDefinesByType 1. GlobalId [1:1] 2. OwnerHistory [0:1] 3. Name [0:1] 4. Description [0:1] 5. RelatedObjects [1:?] RelatingType 6. RelatingType [1:1] IfcObject:IsTypedBy1->IfcRelDefinesByType:RelatedObjects0 IfcTypeObject IfcTypeObject 1. GlobalId [1:1] 2. OwnerHistory [0:1] TypeName 3. Name [0:1] 4. Description [0:1]      HasAssignments [0:?]      Nests [0:1]      IsNestedBy [0:?]      HasContext [0:1]      IsDecomposedBy [0:?]      Decomposes [0:1]      HasAssociations [0:?] 5. ApplicableOccurrence [0:1] 6. HasPropertySets [1:?]      Types [0:1] IfcRelDefinesByType:RelatingType1->IfcTypeObject:IfcTypeObject0
Figure 4.6.1.A

General Usage

ApplicableEntity
RelatingType
IfcRelDefinesByType.RelatingType
IfcActuator IfcActuatorType
IfcAirTerminalBox IfcAirTerminalBoxType
IfcAirTerminal IfcAirTerminalType
IfcAirToAirHeatRecovery IfcAirToAirHeatRecoveryType
IfcAlarm IfcAlarmType
IfcAudioVisualAppliance IfcAudioVisualApplianceType
IfcBeam IfcBeamType
IfcBearing IfcBearingType
IfcBoiler IfcBoilerType
IfcBuildingElementPart IfcBuildingElementPartType
IfcBuildingElementProxy IfcBuildingElementProxyType
IfcBuiltElement IfcBuiltElementType
IfcBurner IfcBurnerType
IfcCableCarrierFitting IfcCableCarrierFittingType
IfcCableCarrierSegment IfcCableCarrierSegmentType
IfcCableFitting IfcCableFittingType
IfcCableSegment IfcCableSegmentType
IfcCaissonFoundation IfcCaissonFoundationType
IfcChiller IfcChillerType
IfcChimney IfcChimneyType
IfcCivilElement IfcCivilElementType
IfcCoil IfcCoilType
IfcColumn IfcColumnType
IfcCommunicationsAppliance IfcCommunicationsApplianceType
IfcCompressor IfcCompressorType
IfcCondenser IfcCondenserType
IfcConstructionEquipmentResource IfcConstructionEquipmentResourceType
IfcConstructionMaterialResource IfcConstructionMaterialResourceType
IfcConstructionProductResource IfcConstructionProductResourceType
IfcConstructionResource IfcConstructionResourceType
IfcController IfcControllerType
IfcConveyorSegment IfcConveyorSegmentType
IfcCooledBeam IfcCooledBeamType
IfcCoolingTower IfcCoolingTowerType
IfcCourse IfcCourseType
IfcCovering IfcCoveringType
IfcCrewResource IfcCrewResourceType
IfcCurtainWall IfcCurtainWallType
IfcDamper IfcDamperType
IfcDeepFoundation IfcDeepFoundationType
IfcDiscreteAccessory IfcDiscreteAccessoryType
IfcDistributionBoard IfcDistributionBoardType
IfcDistributionChamberElement IfcDistributionChamberElementType
IfcDistributionControlElement IfcDistributionControlElementType
IfcDistributionElement IfcDistributionElementType
IfcDistributionFlowElement IfcDistributionFlowElementType
IfcDoor IfcDoorType
IfcDuctFitting IfcDuctFittingType
IfcDuctSegment IfcDuctSegmentType
IfcDuctSilencer IfcDuctSilencerType
IfcElectricAppliance IfcElectricApplianceType
IfcElectricDistributionBoard IfcElectricDistributionBoardType
IfcElectricFlowStorageDevice IfcElectricFlowStorageDeviceType
IfcElectricFlowTreatmentDevice IfcElectricFlowTreatmentDeviceType
IfcElectricGenerator IfcElectricGeneratorType
IfcElectricMotor IfcElectricMotorType
IfcElectricTimeControl IfcElectricTimeControlType
IfcElementAssembly IfcElementAssemblyType
IfcElementComponent IfcElementComponentType
IfcElement IfcElementType
IfcEnergyConversionDevice IfcEnergyConversionDeviceType
IfcEngine IfcEngineType
IfcEvaporativeCooler IfcEvaporativeCoolerType
IfcEvaporator IfcEvaporatorType
IfcEvent IfcEventType
IfcFan IfcFanType
IfcFastener IfcFastenerType
IfcFilter IfcFilterType
IfcFireSuppressionTerminal IfcFireSuppressionTerminalType
IfcFlowController IfcFlowControllerType
IfcFlowFitting IfcFlowFittingType
IfcFlowInstrument IfcFlowInstrumentType
IfcFlowMeter IfcFlowMeterType
IfcFlowMovingDevice IfcFlowMovingDeviceType
IfcFlowSegment IfcFlowSegmentType
IfcFlowStorageDevice IfcFlowStorageDeviceType
IfcFlowTerminal IfcFlowTerminalType
IfcFlowTreatmentDevice IfcFlowTreatmentDeviceType
IfcFooting IfcFootingType
IfcFurnishingElement IfcFurnishingElementType
IfcFurniture IfcFurnitureType
IfcGeographicElement IfcGeographicElementType
IfcHeatExchanger IfcHeatExchangerType
IfcHumidifier IfcHumidifierType
IfcImpactProtectionDevice IfcImpactProtectionDeviceType
IfcInterceptor IfcInterceptorType
IfcJunctionBox IfcJunctionBoxType
IfcKerb IfcKerbType
IfcLaborResource IfcLaborResourceType
IfcLamp IfcLampType
IfcLightFixture IfcLightFixtureType
IfcLiquidTerminal IfcLiquidTerminalType
IfcMechanicalFastener IfcMechanicalFastenerType
IfcMedicalDevice IfcMedicalDeviceType
IfcMember IfcMemberType
IfcMobileTelecommunicationsApplianceIfcMobileTelecommunicationsApplianceType
IfcMooringDevice IfcMooringDeviceType
IfcMotorConnection IfcMotorConnectionType
IfcNavigationElement IfcNavigationElementType
IfcObject IfcTypeObject
IfcOutlet IfcOutletType
IfcPavement IfcPavementType
IfcPile IfcPileType
IfcPipeFitting IfcPipeFittingType
IfcPipeSegment IfcPipeSegmentType
IfcPlate IfcPlateType
IfcProcedure IfcProcedureType
IfcProcess IfcTypeProcess
IfcProduct IfcTypeProduct
IfcProtectiveDevice IfcProtectiveDeviceType
IfcProtectiveDeviceTrippingUnit IfcProtectiveDeviceTrippingUnitType
IfcPump IfcPumpType
IfcRailing IfcRailingType
IfcRail IfcRailType
IfcRampFlight IfcRampFlightType
IfcRamp IfcRampType
IfcReinforcingBar IfcReinforcingBarType
IfcReinforcingElement IfcReinforcingElementType
IfcReinforcingMesh IfcReinforcingMeshType
IfcResource IfcTypeResource
IfcRoof IfcRoofType
IfcSanitaryTerminal IfcSanitaryTerminalType
IfcSensor IfcSensorType
IfcShadingDevice IfcShadingDeviceType
IfcSignal IfcSignalType
IfcSign IfcSignType
IfcSlab IfcSlabType
IfcSolarDevice IfcSolarDeviceType
IfcSpaceHeater IfcSpaceHeaterType
IfcSpace IfcSpaceType
IfcSpatialElement IfcSpatialElementType
IfcSpatialStructureElement IfcSpatialStructureElementType
IfcSpatialZone IfcSpatialZoneType
IfcStackTerminal IfcStackTerminalType
IfcStairFlight IfcStairFlightType
IfcStair IfcStairType
IfcSubContractResource IfcSubContractResourceType
IfcSwitchingDevice IfcSwitchingDeviceType
IfcSystemFurnitureElement IfcSystemFurnitureElementType
IfcTank IfcTankType
IfcTask IfcTaskType
IfcTendonAnchor IfcTendonAnchorType
IfcTendonConduit IfcTendonConduitType
IfcTendon IfcTendonType
IfcTrackElement IfcTrackElementType
IfcTransformer IfcTransformerType
IfcTransportElement IfcTransportElementType
IfcTransportationDevice IfcTransportationDeviceType
IfcTubeBundle IfcTubeBundleType
IfcUnitaryControlElement IfcUnitaryControlElementType
IfcUnitaryEquipment IfcUnitaryEquipmentType
IfcValve IfcValveType
IfcVehicle IfcVehicleType
IfcVibrationDamper IfcVibrationDamperType
IfcVibrationIsolator IfcVibrationIsolatorType
IfcWall IfcWallType
IfcWasteTerminal IfcWasteTerminalType
IfcWindow IfcWindowType
Table 4.6.1.B