IfcSpatialElement

Item	SPF	XML	Change	Description
4.0.0.0
IfcSpatialElement			ADDED

Semantic definitions at the entity

Entity definition

A spatial element is the generalization of all spatial elements that might be used to define a spatial structure or to define spatial zones.

a hierarchical spatial structure element as IfcSpatialStructureElement
- a spatial structure is a hiearchical decomposition of the project. That spatial structure is often used to provide a project structure to organize a building project.
- A spatial project structure might define as many levels of decomposition as necessary for the building project. Elements within the spatial project structure are site, building, storey, and space
a spatial zone as IfcSpatialZone
- a spatial zone is a non-hierarchical and potentially overlapping decomposition of the project under some functional consideration.
- a spatial zone might be used to represent a thermal zone, a lighting zone, a usable area zone.
- a spatial zone might be used to represent a horizontal spatial structure as used in civil works.
- a spatial zone might have its independent placement and shape representation.

HISTORY New entity in IFC4.

Attribute definitions

#	Attribute	Type	Cardinality	Description	R
8	LongName	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 spacial element, and the LongName refers to the full descriptive name.	X
	ContainsElements	IfcRelContainedInSpatialStructure @RelatingStructure	S[0:?]	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.	X
	ServicedBySystems	IfcRelServicesBuildings @RelatedBuildings	S[0:?]	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.	X

Inherited definitions from supertypes

Entity inheritance

Attribute inheritance

#	Attribute	Type	Cardinality	Description	R
IfcRoot
1	GlobalId	IfcGloballyUniqueId		Assignment of a globally unique identifier within the entire software world.	X
2	OwnerHistory	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 in stored - either as addition, deletion or modification. IFC4 CHANGE The attribute has been changed to be OPTIONAL.	X
3	Name	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.	X
4	Description	IfcText	?	Optional description, provided for exchanging informative comments.	X
IfcObjectDefinition
	HasAssignments	IfcRelAssigns @RelatedObjects	S[0:?]	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.	X
	Nests	IfcRelNests @RelatedObjects	S[0:1]	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 strutures only). IFC4 CHANGE The inverse attribute datatype has been added and separated from Decomposes defined at IfcObjectDefinition.
	IsNestedBy	IfcRelNests @RelatingObject	S[0:?]	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.	X
	HasContext	IfcRelDeclares @RelatedDefinitions	S[0:1]	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	IfcRelAggregates @RelatingObject	S[0:?]	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 definitions 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.	X
	Decomposes	IfcRelAggregates @RelatedObjects	S[0:1]	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 definitions can only be part of a single decomposition (to allow hierarchical strutures only). IFC4 CHANGE The inverse attribute datatype has been changed from the supertype IfcRelDecomposes to subtype IfcRelAggregates.	X
	HasAssociations	IfcRelAssociates @RelatedObjects	S[0:?]	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.	X
IfcObject
5	ObjectType	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.	X
	IsTypedBy	IfcRelDefinesByType @RelatedObjects	S[0:1]	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 had previously be included in the inverse relationship IfcRelDefines. Change made with upward compatibility for file based exchange.	X
	IsDefinedBy	IfcRelDefinesByProperties @RelatedObjects	S[0:?]	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.	X
IfcProduct
6	ObjectPlacement	IfcObjectPlacement	?	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 constraint (e.g. relative to grid axes). It is determined by the various subtypes of IfcObjectPlacement, which includes the axis placement information to determine the transformation for the object coordinate system.	X
7	Representation	IfcProductRepresentation	?	Reference to the representations of the product, being either a representation (IfcProductRepresentation) or as a special case a shape representations (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.	X
IfcSpatialElement
8	LongName	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 spacial element, and the LongName refers to the full descriptive name.	X
	ContainsElements	IfcRelContainedInSpatialStructure @RelatingStructure	S[0:?]	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.	X
	ServicedBySystems	IfcRelServicesBuildings @RelatedBuildings	S[0:?]	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.	X

Definitions applying to Reference View

Instance diagram

Concept usage

Spatial Element Type Predefined Type

The Spatial Element Type Predefined Type concept applies to this entity.

Property Sets for Objects

The Property Sets for Objects concept template applies to this entity as shown in Table 41.

PsetName

Properties

Pset_ThermalLoadAggregate

Template	PropertyName	Value
Single Value	TotalCoolingLoad	IfcPowerMeasure
Single Value	TotalHeatingLoad	IfcPowerMeasure
Single Value	LightingDiversity	IfcPositiveRatioMeasure
Single Value	InfiltrationDiversitySummer	IfcPositiveRatioMeasure
Single Value	InfiltrationDiversityWinter	IfcPositiveRatioMeasure
Single Value	ApplianceDiversity	IfcPositiveRatioMeasure
Single Value	LoadSafetyFactor	IfcPositiveRatioMeasure

Pset_ThermalLoadDesignCriteria

Template	PropertyName	Value
Single Value	OccupancyDiversity	IfcPositiveRatioMeasure
Single Value	OutsideAirPerPerson	IfcVolumetricFlowRateMeasure
Single Value	ReceptacleLoadIntensity	IfcReal
Single Value	AppliancePercentLoadToRadiant	IfcPositiveRatioMeasure
Single Value	LightingLoadIntensity	IfcReal
Single Value	LightingPercentLoadToReturnAir	IfcPositiveRatioMeasure

Table 41 — IfcSpatialElement Property Sets for Objects

mvdXML Specification


<?xml version="1.0"?>

<ConceptRoot xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" uuid="ff677d4e-7307-46f0-9424-9063ac36a867" name="IfcSpatialElement" status="sample" applicableRootEntity="IfcSpatialElement">

  <Applicability uuid="00000000-0000-0000-0000-000000000000" status="sample">

    <Template ref="673b0d93-bcf9-46ba-b51b-b0e86732d563" />

    <TemplateRules operator="and" />

  </Applicability>

  <Concepts>

    <Concept uuid="40593df6-210e-4d98-af69-4430577704c0" name="Spatial Element Type Predefined Type" status="sample" override="false">

      <Template ref="1a9b609e-a295-4a3f-aed8-588712adce11" />

    </Concept>

    <Concept uuid="2c2e67b0-ce73-4abb-a426-d73e9bcfbc98" name="Property Sets for Objects" status="sample" override="false">

      <Template ref="f74255a6-0c0e-4f31-84ad-24981db62461" />

      <TemplateRules operator="and">

        <TemplateRule Parameters="PsetName=Pset_ThermalLoadAggregate;" />

        <TemplateRule Parameters="PsetName=Pset_ThermalLoadDesignCriteria;" />

      </TemplateRules>

    </Concept>

  </Concepts>

</ConceptRoot>

Concept inheritance

#	Concept	Template	Model View
IfcRoot
	Identity	Software Identity	Reference View
	Revision Control	Revision Control	Reference View
IfcObjectDefinition
	Classification	Classification	Reference View
IfcObject
	Object User Identity	Object User Identity	Reference View
	Object Predefined Type	Object Predefined Type	Reference View
	Object Typing	Object Typing	Reference View
	Property Sets for Objects	Property Sets with Override	Reference View
IfcSpatialElement
	Spatial Element Type Predefined Type	Spatial Element Type Predefined Type	Reference View
	Property Sets for Objects	Property Sets for Objects	Reference View

Formal representations

XML Specification

 <xs:element name="IfcSpatialElement" type="ifc:IfcSpatialElement" abstract="true" substitutionGroup="ifc:IfcProduct" nillable="true"/>

 <xs:complexType name="IfcSpatialElement" abstract="true">

  <xs:complexContent>

   <xs:extension base="ifc:IfcProduct">

    <xs:sequence>

     <xs:element name="ContainsElements" nillable="true" minOccurs="0">

      <xs:complexType>

       <xs:sequence>

        <xs:element ref="ifc:IfcRelContainedInSpatialStructure" minOccurs="0" maxOccurs="unbounded"/>

       </xs:sequence>

       <xs:attribute ref="ifc:itemType" fixed="ifc:IfcRelContainedInSpatialStructure"/>

       <xs:attribute ref="ifc:cType" fixed="set"/>

       <xs:attribute ref="ifc:arraySize" use="optional"/>

      </xs:complexType>

     </xs:element>

    </xs:sequence>

    <xs:attribute name="LongName" type="ifc:IfcLabel" use="optional"/>

   </xs:extension>

  </xs:complexContent>

 </xs:complexType>

EXPRESS Specification


ENTITY IfcSpatialElement

 ABSTRACT SUPERTYPE OF(ONEOF(IfcSpatialStructureElement, IfcSpatialZone))

 SUBTYPE OF (IfcProduct);

  LongName : OPTIONAL IfcLabel;

 INVERSE

  ContainsElements : SET [0:?] OF IfcRelContainedInSpatialStructure FOR RelatingStructure;

  ServicedBySystems : SET [0:?] OF IfcRelServicesBuildings FOR RelatedBuildings;

END_ENTITY;

 EXPRESS-G diagram

	Räumliches Element
	Spatial Element
	Element spatial