6.1.3.32 IfcRoofType

6.1.3.32.1 Semantic definition

The building element type IfcRoofType defines commonly shared information for occurrences of roofs. The set of shared information may include:

common properties with shared property sets
common representations
common materials
common composition of elements

It is used to define a roof type specification indicating the specific product information that is common to all occurrences of that product type. The IfcRoofType may be declared within IfcProject or IfcProjectLibrary using IfcRelDeclares and may be exchanged with or without occurrences of the type. Occurrences of IfcRoofType are represented by instances of IfcRoof. Refer to the documentation at IfcRoof for supported property sets, materials, and composition.

6.1.3.32.2 Entity inheritance

6.1.3.32.3 Attributes

#	Attribute	Type	Description
IfcRoot (4)
1	GlobalId	IfcGloballyUniqueId	Assignment of a globally unique identifier within the entire software world.
2	OwnerHistory	OPTIONAL IfcOwnerHistory	Assignment of the information about the current ownership of that object, including owning actor, application, local identification and information captured about the recent changes of the object, NOTE Only the last modification is stored - either as addition, deletion or modification. IFC4-CHANGE The attribute has been changed to be OPTIONAL.
3	Name	OPTIONAL IfcLabel	Optional name for use by the participating software systems or users. For some subtypes of IfcRoot the insertion of the Name attribute may be required. This would be enforced by a where rule.
4	Description	OPTIONAL IfcText	Optional description, provided for exchanging informative comments.
IfcObjectDefinition (7)
	HasAssignments	SET [0:?] OF IfcRelAssigns FOR RelatedObjects	Reference to the relationship objects, that assign (by an association relationship) other subtypes of IfcObject to this object instance. Examples are the association to products, processes, controls, resources or groups.
	Nests	SET [0:1] OF IfcRelNests FOR RelatedObjects	References to the decomposition relationship being a nesting. It determines that this object definition is a part within an ordered whole/part decomposition relationship. An object occurrence or type can only be part of a single decomposition (to allow hierarchical structures only). IFC4-CHANGE The inverse attribute datatype has been added and separated from Decomposes defined at IfcObjectDefinition.
	IsNestedBy	SET [0:?] OF IfcRelNests FOR RelatingObject	References to the decomposition relationship being a nesting. It determines that this object definition is the whole within an ordered whole/part decomposition relationship. An object or object type can be nested by several other objects (occurrences or types). IFC4-CHANGE The inverse attribute datatype has been added and separated from IsDecomposedBy defined at IfcObjectDefinition.
	HasContext	SET [0:1] OF IfcRelDeclares FOR RelatedDefinitions	References to the context providing context information such as project unit or representation context. It should only be asserted for the uppermost non-spatial object. IFC4-CHANGE The inverse attribute datatype has been added.
	IsDecomposedBy	SET [0:?] OF IfcRelAggregates FOR RelatingObject	References to the decomposition relationship being an aggregation. It determines that this object definition is whole within an unordered whole/part decomposition relationship. An object definition can be aggregated by several other objects (occurrences or parts). IFC4-CHANGE The inverse attribute datatype has been changed from the supertype IfcRelDecomposes to subtype IfcRelAggregates.
	Decomposes	SET [0:1] OF IfcRelAggregates FOR RelatedObjects	References to the decomposition relationship being an aggregation. It determines that this object definition is a part within an unordered whole/part decomposition relationship. An object definition can only be part of a single decomposition (to allow hierarchical structures only). IFC4-CHANGE The inverse attribute datatype has been changed from the supertype IfcRelDecomposes to subtype IfcRelAggregates.
	HasAssociations	SET [0:?] OF IfcRelAssociates FOR RelatedObjects	Reference to the relationship objects, that associates external references or other resource definitions to the object. Examples are the association to library, documentation or classification.
IfcTypeObject (3)
5	ApplicableOccurrence	OPTIONAL IfcIdentifier	The attribute optionally defines the data type of the occurrence object, to which the assigned type object can relate. If not present, no instruction is given to which occurrence object the type object is applicable. The following conventions are used: The IFC entity name of the applicable occurrence using the IFC naming convention, CamelCase with "Ifc" prefix It can be optionally followed by the predefined type after the separator "/" (forward slash), using uppercase If one type object is applicable to many occurrence objects, then those occurrence object names should be separate by comma "," forming a comma separated string. EXAMPLE Referring to a furniture as applicable occurrence entity would be expressed as 'IfcFurnishingElement', referring to a brace as applicable entity would be expressed as 'IfcMember/BRACE'.
6	HasPropertySets	OPTIONAL SET [1:?] OF IfcPropertySetDefinition	Set of unique property sets, that are associated with the object type and are common to all object occurrences referring to this object type. IFC2x3-CHANGE The attribute aggregate type has been changed from LIST to SET.
	Types	SET [0:1] OF IfcRelDefinesByType FOR RelatingType	Reference to the relationship IfcRelDefinesByType and thus to those occurrence objects, which are defined by this type.
IfcTypeProduct (3)
7	RepresentationMaps	OPTIONAL LIST [1:?] OF UNIQUE IfcRepresentationMap	List of unique representation maps. Each representation map describes a block definition of the shape of the product style. By providing more than one representation map, a multi-view block definition can be given.
8	Tag	OPTIONAL IfcLabel	The tag (or label) identifier at the particular type of a product, e.g. the article number (like the EAN). It is the identifier at the specific level.
	ReferencedBy	SET [0:?] OF IfcRelAssignsToProduct FOR RelatingProduct	Reference to the IfcRelAssignsToProduct relationship, by which other products, processes, controls, resources or actors (as subtypes of IfcObjectDefinition) can be related to this product type. IFC4-CHANGE New inverse relationship.
IfcElementType (1)
9	ElementType	OPTIONAL IfcLabel	The type denotes a particular type that indicates the object further. The use has to be established at the level of instantiable subtypes. In particular it holds the user defined type, if the enumeration of the attribute 'PredefinedType' is set to USERDEFINED.
Click to show 18 hidden inherited attributes
IfcRoofType (1)
10	PredefinedType	IfcRoofTypeEnum	Identifies the predefined types of a roof element from which the type required may be set.

Table 6.1.3.32.C

6.1.3.32.4 Formal propositions

Name Description

CorrectPredefinedType

The inherited attribute ElementType shall be provided, if the PredefinedType is set to USERDEFINED.

 (PredefinedType <> IfcRoofTypeEnum.USERDEFINED) OR
 ((PredefinedType = IfcRoofTypeEnum.USERDEFINED) AND EXISTS (SELF\IfcElementType.ElementType))

Table 6.1.3.32.D

6.1.3.32.5 Property sets

Pset_ConcreteElementGeneral
- AssemblyPlace
- CastingMethod
- StructuralClass
- StrengthClass
- ExposureClass
- ReinforcementVolumeRatio
- ReinforcementAreaRatio
- DimensionalAccuracyClass
- ConstructionToleranceClass
- ConcreteCover
- ConcreteCoverAtMainBars
- ConcreteCoverAtLinks
- ReinforcementStrengthClass
Pset_Condition
- AssessmentDate
- AssessmentCondition
- AssessmentDescription
- AssessmentType
- AssessmentMethod
- LastAssessmentReport
- NextAssessmentDate
- AssessmentFrequency
Pset_ConstructionAdministration
- ProcurementMethod
- SpecificationSectionNumber
- SubmittalIdentifer
Pset_ElementKinematics
- CyclicPath
- CyclicRange
- LinearPath
- LinearRange
- MaximumAngularVelocity
- MaximumConstantSpeed
- MinimumTime
Pset_EnvironmentalCondition
- ReferenceAirRelativeHumidity
- ReferenceEnvironmentTemperature
- MaximumAtmosphericPressure
- StorageTemperatureRange
- MaximumWindSpeed
- OperationalTemperatureRange
- MaximumRainIntensity
- SaltMistLevel
- SeismicResistance
- SmokeLevel
- MaximumSolarRadiation
Pset_EnvironmentalImpactIndicators
- Reference
- FunctionalUnitReference
- IndicatorsUnit
- LifeCyclePhase
- ExpectedServiceLife
- TotalPrimaryEnergyConsumptionPerUnit
- WaterConsumptionPerUnit
- HazardousWastePerUnit
- NonHazardousWastePerUnit
- ClimateChangePerUnit
- AtmosphericAcidificationPerUnit
- RenewableEnergyConsumptionPerUnit
- NonRenewableEnergyConsumptionPerUnit
- ResourceDepletionPerUnit
- InertWastePerUnit
- RadioactiveWastePerUnit
- StratosphericOzoneLayerDestructionPerUnit
- PhotochemicalOzoneFormationPerUnit
- EutrophicationPerUnit
Pset_EnvironmentalImpactValues
- TotalPrimaryEnergyConsumption
- WaterConsumption
- HazardousWaste
- NonHazardousWaste
- ClimateChange
- AtmosphericAcidification
- RenewableEnergyConsumption
- NonRenewableEnergyConsumption
- ResourceDepletion
- InertWaste
- RadioactiveWaste
- StratosphericOzoneLayerDestruction
- PhotochemicalOzoneFormation
- Eutrophication
- LeadInTime
- Duration
- LeadOutTime
Pset_MaintenanceStrategy
- AssetCriticality
- AssetFrailty
- AssetPriority
- MonitoringType
- AccidentResponse
Pset_MaintenanceTriggerCondition
- ConditionTargetPerformance
- ConditionMaintenanceLevel
- ConditionReplacementLevel
- ConditionDisposalLevel
Pset_MaintenanceTriggerDuration
- DurationTargetPerformance
- DurationMaintenanceLevel
- DurationReplacementLevel
- DurationDisposalLevel
Pset_MaintenanceTriggerPerformance
- TargetPerformance
- PerformanceMaintenanceLevel
- ReplacementLevel
- DisposalLevel
Pset_ManufacturerTypeInformation
- GlobalTradeItemNumber
- ArticleNumber
- ModelReference
- ModelLabel
- Manufacturer
- ProductionYear
- AssemblyPlace
- OperationalDocument
- SafetyDocument
- PerformanceCertificate
Pset_PrecastConcreteElementFabrication
- TypeDesignation
- ProductionLotId
- SerialNumber
- PieceMark
- AsBuiltLocationNumber
- ActualProductionDate
- ActualErectionDate
Pset_PrecastConcreteElementGeneral
- TypeDesignation
- CornerChamfer
- ManufacturingToleranceClass
- FormStrippingStrength
- LiftingStrength
- ReleaseStrength
- MinimumAllowableSupportLength
- InitialTension
- TendonRelaxation
- TransportationStrength
- SupportDuringTransportDescription
- SupportDuringTransportDocReference
- HollowCorePlugging
- CamberAtMidspan
- BatterAtStart
- BatterAtEnd
- Twisting
- Shortening
- PieceMark
- DesignLocationNumber
Pset_Risk
- RiskName
- RiskType
- NatureOfRisk
- RiskAssessmentMethodology
- UnmitigatedRiskLikelihood
- UnmitigatedRiskConsequence
- UnmitigatedRiskSignificance
- MitigationPlanned
- MitigatedRiskLikelihood
- MitigatedRiskConsequence
- MitigatedRiskSignificance
- MitigationProposed
- AssociatedProduct
- AssociatedActivity
- AssociatedLocation
Pset_RoofCommon
- Reference
- Status
- AcousticRating
- IsExternal
- ThermalTransmittance
- FireRating
- LoadBearing
Pset_ServiceLife
- ServiceLifeDuration
- MeanTimeBetweenFailure
Pset_Tolerance
- ToleranceDescription
- ToleranceBasis
- OverallTolerance
- HorizontalTolerance
- OrthogonalTolerance
- VerticalTolerance
- PlanarFlatness
- HorizontalFlatness
- ElevationalFlatness
- SideFlatness
- OverallOrthogonality
- HorizontalOrthogonality
- OrthogonalOrthogonality
- VerticalOrthogonality
- OverallStraightness
- HorizontalStraightness
- OrthogonalStraightness
- VerticalStraightness
Pset_Uncertainty
- UncertaintyBasis
- UncertaintyDescription
- HorizontalUncertainty
- LinearUncertainty
- OrthogonalUncertainty
- VerticalUncertainty
Pset_Warranty
- WarrantyIdentifier
- WarrantyStartDate
- IsExtendedWarranty
- WarrantyPeriod
- WarrantyContent
- PointOfContact
- Exclusions
Qto_RoofBaseQuantities
- GrossArea
- NetArea
- ProjectedArea

6.1.3.32.6 Concept usage

representation map — Figure 6.1.3.32.A — Product type geometry with single placement

Concept	Usage	Description
IfcRoot (2)
Revision Control	General	Ownership, history, and merge state is captured using IfcOwnerHistory.
Software Identity	General	IfcRoot assigns the globally unique ID. In addition it may provide for a name and a description about the concept.
IfcObjectDefinition (9)
Classification Association	General	Any object occurrence or object type can have a reference to a specific classification reference, i.e. to a particular facet within a classification system.
Aggregation	General	No description available.
Approval Association	General	No description available.
Constraint Association	General	No description available.
Document Association	General	No description available.
Library Association	General	No description available.
Material Association	General	No description available.
Material Single	General	No description available.
Nesting	General	No description available.
IfcTypeObject (2)
Object Type Predefined Type	General	No description available.
Property Sets for Types	General	No description available.
IfcTypeProduct (7)
Product Type Shape	General	The RepresentationMaps define the type product shape and multiple geometric representations can be assigned. If a product occurrence is assigned to the type by using the IfcRelDefinesByType relationship, then these occurrences have to reference the representation maps. The reference is created by one or multiple IfcShapeRepresentation's having an IfcMappedItem as Items, that places the IfcRepresentationMap of the type product into the spatial contexts, i.e. by using a Cartesian transformation operator to transform the IfcRepresentationMap into the object coordinate system of the product occurrence. Figure 6.1.3.32.A illustrates an example of referencing a representation map by the shape representation of a product occurrence. Here the Cartesian transformation operator only uses translation, but no rotation, mirroring, or scaling. Figure 6.1.3.32.A — Product type geometry with single placement Figure 6.1.3.32.B illustrates an example of referencing a representation multiple times by the shape representation of a product occurrence. Here the Cartesian transformation operator only uses translation, but no rotation, mirroring, or scaling. The different translation values determine the pattern of the multiple placement. Figure 6.1.3.32.B — Product type geometry with multiple placement
Product Type Geometric Representation	General	No description available.
Property Sets for Objects	General	This concept can be applied to the following resources: Pset_Risk Pset_Tolerance Pset_Uncertainty
Type Body AdvancedBrep Geometry	General	No description available.
Type Body Brep Geometry	General	No description available.
Type Body CSG Geometry	General	No description available.
Type Body Geometry	General	No description available.
IfcElementType (5)
Element Type Predefined Type	General	No description available.
Type Body Tessellated Geometry	General	No description available.
Type Element Aggregation	General	No description available.
Property Sets for Objects	General	This concept can be applied to the following resources: Pset_Condition Pset_MaintenanceStrategy Pset_MaintenanceTriggerCondition Pset_MaintenanceTriggerDuration Pset_MaintenanceTriggerPerformance Pset_ConstructionAdministration Pset_ElementKinematics Pset_EnvironmentalCondition Pset_EnvironmentalImpactIndicators Pset_EnvironmentalImpactValues Pset_ManufacturerTypeInformation Pset_ServiceLife Pset_Warranty
Type Element Nesting	General	No description available.
Click to show 25 hidden inherited concepts
IfcRoofType (2)
Property Sets for Objects	General	This is a further elaboration on an inherited concept. This concept can be applied to the following resources: Pset_ConcreteElementGeneral Pset_PrecastConcreteElementFabrication Pset_PrecastConcreteElementGeneral Pset_RoofCommon
Quantity Sets	General	This concept can be applied to the following resources: Qto_RoofBaseQuantities

6.1.3.32.7 Formal representation

 ENTITY IfcRoofType
 SUBTYPE OF (IfcBuiltElementType);
	PredefinedType : IfcRoofTypeEnum;
 WHERE
	CorrectPredefinedType : (PredefinedType <> IfcRoofTypeEnum.USERDEFINED) OR
 ((PredefinedType = IfcRoofTypeEnum.USERDEFINED) AND EXISTS (SELF\IfcElementType.ElementType));
END_ENTITY;

6.1.3.32.8 References

IfcBuiltElementType