5.4.3.68 IfcSpatialStructureElement

ABSTRACT This definition may not be instantiated

5.4.3.68.1 Semantic definition

A spatial structure element is the generalization of all spatial elements that might be used to define a spatial structure. The spatial structure can be used to provide a spatial organization of a project.

A spatial project structure might define as many levels of decomposition as necessary for the project. Elements within the spatial project structure are:

site as IfcSite
facility as IfcFacility, or specifically
building as IfcBuilding
bridge as IfcBridge
marine facility as IfcMarineFacility
railway as IfcRailway
road as IfcRoad
facility part as IfcFacilityPart, or specifically
storey as IfcBuildingStorey
facility part as IfcFacilityPart
space as IfcSpace

or aggregations or parts thereof. The composition type declares an element to be either an element itself, or an aggregation (complex) or a decomposition (part). The interpretation of these types is given at each subtype of IfcSpatialStructureElement.

The IfcRelAggregates is defined as an 1-to-many relationship and used to establish the relationship between exactly two levels within the spatial project structure. Finally the highest level of the spatial structure is assigned to IfcProject using the IfcRelAggregates.

The subtypes of IfcSpatialStructureElement relate to other elements and systems by establishing the following relationships:

Containment of elements : IfcRelContainedInSpatialStructure by inverse attribute ContainsElements, used to assign any element, like building elements, MEP elements, etc. to the spatial structure element in which they are primarily contained.
Reference of elements : IfcRelReferencedInSpatialStructure by inverse attribute ReferencesElements, used to reference any element, like building elements, MEP elements, etc. in spatial structure elements, other then the one, where it is contained. Since the deprecation of IfcRelServicesBuildings, IfcRelReferencedInSpatialStructure is also used to reference a system, like a building service or electrical distribution system, a zonal system, or a structural analysis system, that is assigned to this spatial structure element.

The subtypes of IfcSpatialStructureElement relate to each other by using the IfcRelAggregates relationship to build the project spatial structure. Figure 5.4.3.68.A shows the use of IfcRelAggregates to establish a spatial structure including site, building, building section and storey. More information is provided at the level of the subtypes.

fig1 — Figure 5.4.3.68.A — Spatial structure element composition

Informal Propositions

The spatial project structure, established by the IfcRelAggregates, shall be acyclic.
A site should not be (directly or indirectly) associated to a building, storey or space.
A building should not be (directly or indirectly) associated to a storey or space.
A storey should not be (directly or indirectly) associated to a space.

5.4.3.68.2 Entity inheritance

5.4.3.68.3 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.
IfcObject (5)
5	ObjectType	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 or when the concrete entity instantiated does not have a PredefinedType attribute. The latter is the case in some exceptional leaf classes and when instantiating IfcBuiltElement directly.
	IsDeclaredBy	SET [0:1] OF IfcRelDefinesByObject FOR RelatedObjects	Link to the relationship object pointing to the declaring object that provides the object definitions for this object occurrence. The declaring object has to be part of an object type decomposition. The associated IfcObject, or its subtypes, contains the specific information (as part of a type, or style, definition), that is common to all reflected instances of the declaring IfcObject, or its subtypes. IFC4-CHANGE New inverse relationship, change made with upward compatibility for file based exchange.
	Declares	SET [0:?] OF IfcRelDefinesByObject FOR RelatingObject	Link to the relationship object pointing to the reflected object(s) that receives the object definitions. The reflected object has to be part of an object occurrence decomposition. The associated IfcObject, or its subtypes, provides the specific information (as part of a type, or style, definition), that is common to all reflected instances of the declaring IfcObject, or its subtypes. IFC4-CHANGE New inverse relationship, change made with upward compatibility for file based exchange.
	IsTypedBy	SET [0:1] OF IfcRelDefinesByType FOR RelatedObjects	Set of relationships to the object type that provides the type definitions for this object occurrence. The then associated IfcTypeObject, or its subtypes, contains the specific information (or type, or style), that is common to all instances of IfcObject, or its subtypes, referring to the same type. IFC4-CHANGE New inverse relationship, the link to IfcRelDefinesByType was previously included in the inverse relationship IfcRelDefines. Change made with upward compatibility for file based exchange.
	IsDefinedBy	SET [0:?] OF IfcRelDefinesByProperties FOR RelatedObjects	Set of relationships to property set definitions attached to this object. Those statically or dynamically defined properties contain alphanumeric information content that further defines the object. IFC4-CHANGE The data type has been changed from IfcRelDefines to IfcRelDefinesByProperties with upward compatibility for file based exchange.
IfcProduct (5)
6	ObjectPlacement	OPTIONAL IfcObjectPlacement	This establishes the object coordinate system and placement of the product in space. The placement can either be absolute (relative to the world coordinate system), relative (relative to the object placement of another product), or constrained (e.g. relative to grid axes, or to a linear positioning element). The type of placement is determined by the various subtypes of IfcObjectPlacement. An object placement must be provided if a representation is present.
7	Representation	OPTIONAL IfcProductRepresentation	Reference to the representations of the product, being either a representation (IfcProductRepresentation) or as a special case of a shape representation (IfcProductDefinitionShape). The product definition shape provides for multiple geometric representations of the shape property of the object within the same object coordinate system, defined by the object placement.
	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.
	PositionedRelativeTo	SET [0:?] OF IfcRelPositions FOR RelatedProducts	Reference to the IfcRelPositions relationship, which defines its relationship with a positioning element.
	ReferencedInStructures	SET [0:?] OF IfcRelReferencedInSpatialStructure FOR RelatedElements	Reference to the objectified relationship IfcRelReferencedInSpatialStructure may be used to relate a product to one or more spatial structure elements in addition to the one in which it is primarily contained.
IfcSpatialElement (6)
8	LongName	OPTIONAL IfcLabel	Long name for a spatial structure element, used for informal purposes. It should be used, if available, in conjunction with the inherited Name attribute. NOTE In many scenarios the Name attribute refers to the short name or number of a spatial element, and the LongName refers to the full descriptive name.
	ContainsElements	SET [0:?] OF IfcRelContainedInSpatialStructure FOR RelatingStructure	Set of spatial containment relationships, that holds those elements, which are contained within this element of the project spatial structure. NOTE The spatial containment relationship, established by IfcRelContainedInSpatialStructure, is required to be an hierarchical relationship, where each element can only be assigned to 0 or 1 spatial structure element.
	ServicedBySystems	SET [0:?] OF IfcRelServicesBuildings FOR RelatedBuildings	Set of relationships to systems, that provides a certain service to the spatial element for which it is defined. The relationship is handled by the objectified relationship IfcRelServicesBuildings. IFC4-CHANGE The inverse attribute has been promoted to the new supertype IfcSpatialElement with upward compatibility for file based exchange.
	ReferencesElements	SET [0:?] OF IfcRelReferencedInSpatialStructure FOR RelatingStructure	Set of spatial reference relationships, that holds those elements, which are referenced, but not contained, within this element of the project spatial structure. NOTE The spatial reference relationship, established by IfcRelReferencedInSpatialStructure, is not required to be an hierarchical relationship, i.e. each element can be assigned to 0, 1 or many spatial structure elements. EXAMPLE A curtain wall maybe contained in the ground floor, but maybe referenced in all floors, it reaches. IFC2x3-CHANGE The inverse attribute has been added with upward compatibility for file based exchange.
	IsInterferedByElements	SET [0:?] OF IfcRelInterferesElements FOR RelatedElement	Reference to the interference relationship to indicate the spatial element that is interfered. The relationship, if provided, indicates that this spatial element has an interference with one or many other spatial elements. NOTE There is no indication of precedence between IsInterferedByElements and InterferesElements. Orientated interference is defined by IfcRelInterferesElements.ImpliedOrder or IfcRelInterferesElements.InterferenceType. IFC4x3-CHANGE New inverse relationship.
	InterferesElements	SET [0:?] OF IfcRelInterferesElements FOR RelatingElement	Reference to the interference relationship to indicate the spatial element that interferes. The relationship, if provided, indicates that this spatial element has an interference with one or many other spatial elements. NOTE There is no indication of precedence between IsInterferedByElements and InterferesElements. Orientated interference is defined by IfcRelInterferesElements.ImpliedOrder or IfcRelInterferesElements.InterferenceType. IFC4x3-CHANGE New inverse relationship.
Click to show 27 hidden inherited attributes
IfcSpatialStructureElement (1)
9	CompositionType	OPTIONAL IfcElementCompositionEnum	Denotes, whether the predefined spatial structure element represents itself, or an aggregate (complex) or a part (part). The interpretation is given separately for each subtype of spatial structure element. If no CompositionType is asserted, the default value ''ELEMENT'' applies. IFC4-CHANGE Attribute made optional.

Table 5.4.3.68.B

5.4.3.68.4 Formal propositions

Name Description

WR41

All spatial structure elements shall be associated (using the IfcRelAggregates relationship) with another spatial structure element, or with IfcProject.

 (HIINDEX(SELF\IfcObjectDefinition.Decomposes) = 1) 
AND
('IFC4X3_DEV_d5336fff.IFCRELAGGREGATES' IN TYPEOF(SELF\IfcObjectDefinition.Decomposes[1])) 
AND
(('IFC4X3_DEV_d5336fff.IFCPROJECT' IN TYPEOF (SELF\IfcObjectDefinition.Decomposes[1].RelatingObject)) OR
 ('IFC4X3_DEV_d5336fff.IFCSPATIALSTRUCTUREELEMENT' IN TYPEOF (SELF\IfcObjectDefinition.Decomposes[1].RelatingObject))
)

Table 5.4.3.68.C

5.4.3.68.5 Property sets

Pset_AirSideSystemInformation
- Description
- AirSideSystemType
- AirSideSystemDistributionType
- TotalAirFlow
- EnergyGainTotal
- AirFlowSensible
- EnergyGainSensible
- EnergyLoss
- InfiltrationDiversitySummer
- InfiltrationDiversityWinter
- ApplianceDiversity
- HeatingTemperatureDelta
- CoolingTemperatureDelta
- Ventilation
- FanPower
Pset_PropertyAgreement
- AgreementType
- TrackingIdentifier
- AgreementVersion
- AgreementDate
- PropertyName
- CommencementDate
- TerminationDate
- Duration
- Options
- ConditionCommencement
- Restrictions
- ConditionTermination
Pset_Risk
- RiskName
- RiskType
- NatureOfRisk
- RiskAssessmentMethodology
- UnmitigatedRiskLikelihood
- UnmitigatedRiskConsequence
- UnmitigatedRiskSignificance
- MitigationPlanned
- MitigatedRiskLikelihood
- MitigatedRiskConsequence
- MitigatedRiskSignificance
- MitigationProposed
- AssociatedProduct
- AssociatedActivity
- AssociatedLocation
Pset_SpaceAirHandlingDimensioning
- CoolingDesignAirFlow
- HeatingDesignAirFlow
- SensibleHeatGain
- TotalHeatGain
- TotalHeatLoss
- CoolingDryBulb
- CoolingRelativeHumidity
- HeatingDryBulb
- HeatingRelativeHumidity
- VentilationDesignAirFlow
- DesignAirFlow
- CeilingRAPlenum
- BoundaryAreaHeatLoss
Pset_SpaceCommon
- Reference
- IsExternal
- GrossPlannedArea
- NetPlannedArea
- PubliclyAccessible
- HandicapAccessible
Pset_SpaceCoveringRequirements
- FloorCovering
- FloorCoveringThickness
- WallCovering
- WallCoveringThickness
- CeilingCovering
- CeilingCoveringThickness
- SkirtingBoard
- SkirtingBoardHeight
- Molding
- MoldingHeight
- ConcealedFlooring
- ConcealedFlooringOffset
- ConcealedCeiling
- ConcealedCeilingOffset
Pset_SpaceFireSafetyRequirements
- FireRiskFactor
- FlammableStorage
- FireExit
- SprinklerProtection
- SprinklerProtectionAutomatic
- AirPressurization
Pset_SpaceHVACDesign
- TemperatureSetPoint
- TemperatureMax
- TemperatureMin
- TemperatureSummerMax
- TemperatureSummerMin
- TemperatureWinterMax
- TemperatureWinterMin
- HumiditySetPoint
- HumidityMax
- HumidityMin
- HumiditySummer
- HumidityWinter
- DiscontinuedHeating
- NaturalVentilation
- NaturalVentilationRate
- MechanicalVentilation
- MechanicalVentilationRate
- AirConditioning
- AirConditioningCentral
- AirHandlingName
Pset_SpaceLightingDesign
- ArtificialLighting
- Illuminance
Pset_SpaceOccupancyRequirements
- OccupancyType
- OccupancyNumber
- OccupancyNumberPeak
- OccupancyTimePerDay
- AreaPerOccupant
- MinimumHeadroom
- IsOutlookDesirable
Pset_SpaceThermalLoad
- People
- Lighting
- EquipmentSensible
- VentilationIndoorAir
- VentilationOutdoorAir
- RecirculatedAir
- ExhaustAir
- AirExchangeRate
- DryBulbTemperature
- RelativeHumidity
- InfiltrationSensible
- TotalSensibleLoad
- TotalLatentLoad
- TotalRadiantLoad
Pset_SpaceThermalLoadPHistory
- PeopleHistory
- LightingHistory
- EquipmentSensibleHistory
- VentilationIndoorAirHistory
- VentilationOutdoorAirHistory
- RecirculatedAirHistory
- ExhaustAirHistory
- AirExchangeRateTimeHistory
- DryBulbTemperatureHistory
- RelativeHumidityHistory
- InfiltrationSensibleHistory
- TotalSensibleLoadHistory
- TotalLatentLoadHistory
- TotalRadiantLoadHistory
Pset_SpaceThermalPHistory
- CoolingAirFlowRate
- HeatingAirFlowRate
- VentilationAirFlowRateHistory
- ExhaustAirFlowRate
- SpaceTemperatureHistory
- SpaceRelativeHumidity
Pset_ThermalLoad
- OccupancyDiversity
- LightingDiversity
- ApplianceDiversity
- OutsideAirPerPerson
- ReceptacleLoadIntensity
- AppliancePercentLoadToRadiant
- LightingLoadIntensity
- LightingPercentLoadToReturnAir
- TotalCoolingLoad
- TotalHeatingLoad
- InfiltrationDiversitySummer
- InfiltrationDiversityWinter
- LoadSafetyFactor
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
Qto_BodyGeometryValidation
- GrossSurfaceArea
- NetSurfaceArea
- GrossVolume
- NetVolume
- SurfaceGenusBeforeFeatures
- SurfaceGenusAfterFeatures

5.4.3.68.6 Concept usage

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.
IfcObject (5)
Object Predefined Type	General	No description available.
Object Typing	General	Any object occurrence can be typed by being assigned to a common object type utilizing this concept. A particular rule, restricting the applicable subtypes of IfcTypeObject that can be assigned, is introduced by overriding this concept at the level of subtypes of IfcObject. This concept can be applied to the following resources: IfcTypeObject
Object User Identity	General	An attribute Name and optionally Description can be used for all subypes of IfcObject. For those subtypes, that have an object type definition, such as IfcBeam - IfcBeamType, the common Name and optionally Description is associated with the object type.
Property Sets with Override	General	Any object occurrence can hold property sets, either directly at the object occurrence as element specific property sets, or at the object type, as type property sets. In this case, the properties that are provided to the object occurrence are the combinations of element specific and type properties. In case that the same property (within the same property set) is defined both in occurrence and type properties, the property value of the occurrence property overrides the property value of the type property.
Assignment to Group	General	No description available.
IfcProduct (18)
Body Geometry	General	The body or solid model geometric representation of an IfcProduct is typically defined using a Tessellation or Brep. Subtypes may provide recommendations on other representation types that may be used. The following attribute values for the IfcShapeRepresentation holding this geometric representation shall be used: IfcShapeRepresentation.RepresentationIdentifier = 'Body' IfcShapeRepresentation.RepresentationType = Typically 'Tessellation' or 'Brep'
Product Geometric Representation	General	The geometric representation of any IfcProduct is provided by the IfcProductDefinitionShape allowing multiple geometric representations. It uses the Product Placement concept utilizing IfcLocalPlacement to establish an object coordinate system, in which all geometric representations are founded. NOTE A detailed specification of how to apply the local placement and which shape representations are applicable is provided at the level of subtypes of IfcProduct and is further determined by the model view definition and implementer agreements.
Product Geometry Colour	General	No description available.
Product Geometry Layer	General	No description available.
Product Relative Positioning	General	If the IfcProduct Product Placement is placed relative to an IfcPositioningElement this relationship covers the information on which IfcPositioningElement positions the IfcProduct.
Product Span Positioning	General	No description available.
Box Geometry	General	No description available.
CoG Geometry	General	No description available.
Mapped Geometry	General	No description available.
Object Typing	General	This is a further elaboration on an inherited concept. This concept can be applied to the following resources: IfcTypeProduct
Product Local Placement	General	No description available.
Product Topology 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
Quantity Sets	General	This concept can be applied to the following resources: Qto_BodyGeometryValidation
Reference Geometry	General	No description available.
Reference SweptSolid Geometry	General	No description available.
Reference SweptSolid PolyCurve Geometry	General	No description available.
Reference Tessellation Geometry	General	No description available.
IfcSpatialElement (11)
Body Geometry	General	This is a further elaboration on an inherited concept. A spatial element will not usually provide a body geometry, instead relying on its constituting elements. A body geometry may be provided if it is necessary to expose an independent geometric representation. This geometry is typically expressed by its exterior elements or volume boundary.
FootPrint GeomSet Geometry	General	No description available.
Group Spatial Connectivity	General	No description available.
Property Sets for Objects	General	This is a further elaboration on an inherited concept. This concept can be applied to the following resources: Pset_AirSideSystemInformation Pset_SpaceFireSafetyRequirements Pset_SpaceAirHandlingDimensioning Pset_SpaceThermalLoad Pset_SpaceCoveringRequirements Pset_SpaceHVACDesign Pset_SpaceLightingDesign Pset_SpaceOccupancyRequirements Pset_SpaceCommon Pset_ThermalLoad
Spatial Interference	General	No description available.
Spatial Interference With Zones	General	No description available.
Object Typing	General	This is a further elaboration on an inherited concept. This concept can be applied to the following resources: IfcSpatialElementType
Property Sets for Performance	General	This concept can be applied to the following resources: Pset_SpaceThermalLoadPHistory Pset_SpaceThermalPHistory
Spatial Container	General	This concept can be applied to the following resources: IfcAnnotation IfcElement IfcGrid
Spatial Element Attributes	General	No description available.
Spatial Service Connectivity	General	No description available.
Click to show 45 hidden inherited concepts
IfcSpatialStructureElement (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_PropertyAgreement
Object Typing	General	This is a further elaboration on an inherited concept. This concept can be applied to the following resources: IfcSpatialStructureElementType

Table 5.4.3.68.D

5.4.3.68.7 Formal representation

 ENTITY IfcSpatialStructureElement
 ABSTRACT SUPERTYPE OF (ONEOF
	(IfcBuildingStorey
	,IfcFacility
	,IfcFacilityPart
	,IfcSite
	,IfcSpace))
 SUBTYPE OF (IfcSpatialElement);
	CompositionType : OPTIONAL IfcElementCompositionEnum;
 WHERE
	WR41 : (HIINDEX(SELF\IfcObjectDefinition.Decomposes) = 1) 
AND
('IFC4X3_DEV_d5336fff.IFCRELAGGREGATES' IN TYPEOF(SELF\IfcObjectDefinition.Decomposes[1])) 
AND
(('IFC4X3_DEV_d5336fff.IFCPROJECT' IN TYPEOF (SELF\IfcObjectDefinition.Decomposes[1].RelatingObject)) OR
 ('IFC4X3_DEV_d5336fff.IFCSPATIALSTRUCTUREELEMENT' IN TYPEOF (SELF\IfcObjectDefinition.Decomposes[1].RelatingObject))
);
END_ENTITY;