IfcStair

Item	XML	Change	Description
IFC2x3 to IFC4
IfcStair
OwnerHistory		MODIFIED	Instantiation changed to OPTIONAL.
PredefinedType	X	MODIFIED	Name changed from ShapeType to PredefinedType. Instantiation changed to OPTIONAL.

#	Attribute	Type	Cardinality	Description	C
9	PredefinedType	IfcStairTypeEnum	[0:1]	Predefined generic type for a stair that is specified in an enumeration. There may be a property set given specifically for the predefined types. NOTE The PredefinedType shall only be used, if no IfcStairType is assigned, providing its own IfcStairType.PredefinedType.	X

Rule	Description
CorrectPredefinedType	Either the PredefinedType attribute is unset (e.g. because an IfcStairType is associated), or the inherited attribute ObjectType shall be provided, if the PredefinedType is set to USERDEFINED.
CorrectTypeAssigned	Either there is no stair type object associated, i.e. the IsTypedBy inverse relationship is not provided, or the associated type object has to be of type IfcStairType.

Inherited definitions from supertypes

Entity inheritance

Attribute inheritance

#	Attribute	Type	Cardinality	Description	C
IfcRoot
1	GlobalId	IfcGloballyUniqueId	[1:1]	Assignment of a globally unique identifier within the entire software world.	X
2	OwnerHistory	IfcOwnerHistory	[0:1]	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.	X
3	Name	IfcLabel	[0:1]	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	[0:1]	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).	X
	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).	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.	X
	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).	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).	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	[0:1]	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
	IsDeclaredBy	IfcRelDefinesByObject @RelatedObjects	S[0:1]	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.	X
	Declares	IfcRelDefinesByObject @RelatingObject	S[0:?]	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.	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.	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.	X
IfcProduct
6	ObjectPlacement	IfcObjectPlacement	[0:1]	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	[0:1]	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
	ReferencedBy	IfcRelAssignsToProduct @RelatingProduct	S[0:?]	Reference to the IfcRelAssignsToProduct relationship, by which other products, processes, controls, resources or actors (as subtypes of IfcObjectDefinition) can be related to this product.	X
IfcElement
8	Tag	IfcIdentifier	[0:1]	The tag (or label) identifier at the particular instance of a product, e.g. the serial number, or the position number. It is the identifier at the occurrence level.	X
	FillsVoids	IfcRelFillsElement @RelatedBuildingElement	S[0:1]	Reference to the IfcRelFillsElement Relationship that puts the element as a filling into the opening created within another element.	X
	ConnectedTo	IfcRelConnectsElements @RelatingElement	S[0:?]	Reference to the element connection relationship. The relationship then refers to the other element to which this element is connected to.	X
	IsInterferedByElements	IfcRelInterferesElements @RelatedElement	S[0:?]	Reference to the interference relationship to indicate the element that is interfered. The relationship, if provided, indicates that this element has an interference with one or many other elements. NOTE There is no indication of precedence between IsInterferedByElements and InterferesElements.	X
	InterferesElements	IfcRelInterferesElements @RelatingElement	S[0:?]	Reference to the interference relationship to indicate the element that interferes. The relationship, if provided, indicates that this element has an interference with one or many other elements. NOTE There is no indication of precedence between IsInterferedByElements and InterferesElements.	X
	HasProjections	IfcRelProjectsElement @RelatingElement	S[0:?]	Projection relationship that adds a feature (using a Boolean union) to the IfcBuildingElement.	X
	ReferencedInStructures	IfcRelReferencedInSpatialStructure @RelatedElements	S[0:?]	Reference relationship to the spatial structure element, to which the element is additionally associated. This relationship may not be hierarchical, an element may be referenced by zero, one or many spatial structure elements.	X
	HasOpenings	IfcRelVoidsElement @RelatingBuildingElement	S[0:?]	Reference to the IfcRelVoidsElement relationship that creates an opening in an element. An element can incorporate zero-to-many openings. For each opening, that voids the element, a new relationship IfcRelVoidsElement is generated.	X
	IsConnectionRealization	IfcRelConnectsWithRealizingElements @RealizingElements	S[0:?]	Reference to the connection relationship with realizing element. The relationship, if provided, assigns this element as the realizing element to the connection, which provides the physical manifestation of the connection relationship.	X
	ProvidesBoundaries	IfcRelSpaceBoundary @RelatedBuildingElement	S[0:?]	Reference to space boundaries by virtue of the objectified relationship IfcRelSpaceBoundary. It defines the concept of an element bounding spaces.	X
	ConnectedFrom	IfcRelConnectsElements @RelatedElement	S[0:?]	Reference to the element connection relationship. The relationship then refers to the other element that is connected to this element.	X
	ContainedInStructure	IfcRelContainedInSpatialStructure @RelatedElements	S[0:1]	Containment relationship to the spatial structure element, to which the element is primarily associated. This containment relationship has to be hierachical, i.e. an element may only be assigned directly to zero or one spatial structure.	X
	HasCoverings	IfcRelCoversBldgElements @RelatingBuildingElement	S[0:?]	Reference to IfcCovering by virtue of the objectified relationship IfcRelCoversBldgElement. It defines the concept of an element having coverings associated.	X
IfcBuildingElement
IfcStair
9	PredefinedType	IfcStairTypeEnum	[0:1]	Predefined generic type for a stair that is specified in an enumeration. There may be a property set given specifically for the predefined types. NOTE The PredefinedType shall only be used, if no IfcStairType is assigned, providing its own IfcStairType.PredefinedType.	X

Definitions applying to Common Use Definitions

Instance diagram

Concept usage

Object Typing

The Object Typing concept applies to this entity as shown in Table 172.

Type
IfcStairType

Table 172 — IfcStair Object Typing

Property Sets for Objects

The Property Sets for Objects concept applies to this entity as shown in Table 173.

PredefinedType

Name

Properties

Pset_StairCommon

Single Value

Name	Value
Reference	IfcIdentifier
NumberOfRiser	IfcCountMeasure
NumberOfTreads	IfcCountMeasure
RiserHeight	IfcPositiveLengthMeasure
TreadLength	IfcPositiveLengthMeasure
NosingLength	IfcLengthMeasure
WalkingLineOffset	IfcPositiveLengthMeasure
TreadLengthAtOffset	IfcPositiveLengthMeasure
TreadLengthAtInnerSide	IfcPositiveLengthMeasure
WaistThickness	IfcPositiveLengthMeasure
RequiredHeadroom	IfcPositiveLengthMeasure
IsExternal	IfcBoolean
FireRating	IfcLabel
FireExit	IfcBoolean
HandicapAccessible	IfcBoolean
HasNonSkidSurface	IfcBoolean

Enumerated Value

Name	Value	Value
Status	IfcLabel	IfcLabel

Pset_ConcreteElementGeneral

Single Value

Name	Value
ConstructionMethod	IfcLabel
StructuralClass	IfcLabel
StrengthClass	IfcLabel
ExposureClass	IfcLabel
ReinforcementVolumeRatio	IfcMassDensityMeasure
ReinforcementAreaRatio	IfcAreaDensityMeasure
DimensionalAccuracyClass	IfcLabel
ConstructionToleranceClass	IfcLabel
ConcreteCover	IfcPositiveLengthMeasure
ConcreteCoverAtMainBars	IfcPositiveLengthMeasure
ConcreteCoverAtLinks	IfcPositiveLengthMeasure
ReinforcementStrengthClass	IfcLabel

Pset_PrecastConcreteElementFabrication

Single Value

Name	Value
TypeDesignator	IfcLabel
ProductionLotId	IfcIdentifier
SerialNumber	IfcIdentifier
PieceMark	IfcLabel
AsBuiltLocationNumber	IfcLabel
ActualProductionDate	IfcDateTime
ActualErectionDate	IfcDateTime

Pset_PrecastConcreteElementGeneral

Single Value

Name	Value
TypeDesignator	IfcLabel
CornerChamfer	IfcPositiveLengthMeasure
ManufacturingToleranceClass	IfcLabel
FormStrippingStrength	IfcPressureMeasure
LiftingStrength	IfcPressureMeasure
ReleaseStrength	IfcPressureMeasure
MinimumAllowableSupportLength	IfcPositiveLengthMeasure
InitialTension	IfcPressureMeasure
TendonRelaxation	IfcPositiveRatioMeasure
TransportationStrength	IfcPressureMeasure
SupportDuringTransportDescription	IfcText
HollowCorePlugging	IfcLabel
CamberAtMidspan	IfcRatioMeasure
BatterAtStart	IfcPlaneAngleMeasure
BatterAtEnd	IfcPlaneAngleMeasure
Twisting	IfcPlaneAngleMeasure
Shortening	IfcRatioMeasure
PieceMark	IfcLabel
DesignLocationNumber	IfcLabel

Pset_EnvironmentalImpactIndicators

Single Value

Name	Value
Reference	IfcIdentifier
FunctionalUnitReference	IfcLabel
Unit	IfcText
ExpectedServiceLife	IfcTimeMeasure
TotalPrimaryEnergyConsumptionPerUnit	IfcEnergyMeasure
WaterConsumptionPerUnit	IfcVolumeMeasure
HazardousWastePerUnit	IfcMassMeasure
NonHazardousWastePerUnit	IfcMassMeasure
ClimateChangePerUnit	IfcMassMeasure
AtmosphericAcidificationPerUnit	IfcMassMeasure
RenewableEnergyConsumptionPerUnit	IfcEnergyMeasure
NonRenewableEnergyConsumptionPerUnit	IfcEnergyMeasure
ResourceDepletionPerUnit	IfcMassMeasure
InertWastePerUnit	IfcMassMeasure
RadioactiveWastePerUnit	IfcMassMeasure
StratosphericOzoneLayerDestructionPerUnit	IfcMassMeasure
PhotochemicalOzoneFormationPerUnit	IfcMassMeasure
EutrophicationPerUnit	IfcMassMeasure

Enumerated Value

Name	Value	Value
LifeCyclePhase	IfcLabel	IfcLabel

Pset_EnvironmentalImpactValues

Single Value

Name	Value
TotalPrimaryEnergyConsumption	IfcEnergyMeasure
WaterConsumption	IfcVolumeMeasure
HazardousWaste	IfcMassMeasure
NonHazardousWaste	IfcMassMeasure
ClimateChange	IfcMassMeasure
AtmosphericAcidification	IfcMassMeasure
RenewableEnergyConsumption	IfcEnergyMeasure
NonRenewableEnergyConsumption	IfcEnergyMeasure
ResourceDepletion	IfcMassMeasure
InertWaste	IfcMassMeasure
RadioactiveWaste	IfcMassMeasure
StratosphericOzoneLayerDestruction	IfcMassMeasure
PhotochemicalOzoneFormation	IfcMassMeasure
Eutrophication	IfcMassMeasure
LeadInTime	IfcDuration
Duration	IfcDuration
LeadOutTime

Pset_Condition

Single Value

Name	Value
AssessmentDate	IfcDate
AssessmentCondition	IfcLabel
AssessmentDescription	IfcText

Pset_ManufacturerOccurrence

Single Value

Name	Value
AcquisitionDate	IfcDate
BarCode	IfcIdentifier
SerialNumber	IfcIdentifier
BatchReference	IfcIdentifier

Enumerated Value

Name	Value	Value
AssemblyPlace	IfcLabel	IfcLabel

Pset_ManufacturerTypeInformation

Single Value

Name	Value
GlobalTradeItemNumber	IfcIdentifier
ArticleNumber	IfcIdentifier
ModelReference	IfcLabel
ModelLabel	IfcLabel
Manufacturer	IfcLabel
ProductionYear	IfcLabel

Enumerated Value

Name	Value	Value
AssemblyPlace	IfcLabel	IfcLabel

Pset_ServiceLife

Single Value

Name	Value
MeanTimeBetweenFailure	IfcDuration

Bounded Value

Name	Value	Value
ServiceLifeDuration	IfcDuration	IfcDuration

Pset_Warranty

Single Value

Name	Value
WarrantyIdentifier	IfcIdentifier
WarrantyStartDate	IfcDate
WarrantyEndDate	IfcDate
IsExtendedWarranty	IfcBoolean
WarrantyPeriod	IfcTimeMeasure
WarrantyContent	IfcText
Exclusions	IfcText

Table 173 — IfcStair Property Sets for Objects

Material Single

The Material Single concept applies to this entity.

The material of the IfcStair is defined by the IfcMaterial and attached by the IfcRelAssociatesMaterial.RelatingMaterial. It is accessible by the inverse HasAssociations relationship.

Material information can also be given at the IfcStairType, defining the common attribute data for all occurrences of the same type. It is then accessible by the inverse IsDefinedBy relationship pointing to IfcStair.HasAssociations and via IfcRelAssociatesMaterial.RelatingMaterial to IfcMaterial. If both are given, then the material directly assigned to IfcStair overrides the material assigned to IfcStairType.

Spatial Containment

The Spatial Containment concept applies to this entity as shown in Table 174.

Structure	Description
IfcBuildingStorey	Default spatial container
IfcBuilding	Spatial container for the element if it cannot be assigned to a building storey
IfcSite	Spatial container for the element in case that it is placed on site (outside of building)

Table 174 — IfcStair Spatial Containment

The IfcStair, as any subtype of IfcBuildingElement, may participate alternatively in one of the two different containment relationships:

the Spatial Containment (defined here), or
the Element Composition.

Element Decomposition

The Element Decomposition concept applies to this entity as shown in Table 175.

RelatedObjects	Description
IfcStairFlight	Stairs may be decomposed into stair flights.
IfcSlab	Stairs may be decomposed into stair landing, represented by IfcSlab.PredefinedType=LANDING
IfcRailing	Stairs may be decomposed into railings for zero, one, or both sides.

Table 175 — IfcStair Element Decomposition

Geometric representation by aggregated elements

If the IfcStair has components (referenced by SELF\IfcObject.IsDecomposedBy) with own 'Body' representation, then no 'Body' representation shall defined for the IfcStair. The IfcStair shape is then represented by the geometric representation of its components. The components are accessed via SELF\IfcObject.IsDecomposedBy[1].RelatedObjects.

Figure 239 illustrates stair placement, where the IfcStair defines the local placement for all components and the common 'Axis' representation, and each component has its own 'Body' representation.

Figure 239 — Stair placement

Product Local Placement

The Product Local Placement concept applies to this entity as shown in Table 176.

Type	Relative	Description
IfcLocalPlacement	IfcLocalPlacement	Relative placement according to position and rotation relative to container.
IfcLocalPlacement		Absolute placement according to position and rotation of world coordinate system.
IfcGridPlacement		Placement according to grid intersection.

Table 176 — IfcStair Product Local Placement

The following restriction may be imposed by view definitions or implementer agreements:

If the IfcStair establishes an aggregate, then all contained elements shall be placed relative to the IfcStair.ObjectPlacement.

Axis 2D Geometry

The Axis 2D Geometry concept applies to this entity.

The walking line is represented by a two-dimensional open curve as the axis. The curve is directed into the upward direction (direction has to be interpreted as specified at the subtypes of IfcCurve).

NOTE The 'Axis' representation of IfcStair may be provided even if the IfcStair has components with own shape representations.

Body SweptSolid Geometry

The Body SweptSolid Geometry concept applies to this entity.

Concept inheritance

#	Concept	Model View
IfcRoot
	Software Identity	Common Use Definitions
	Revision Control	Common Use Definitions
IfcObject
	Object Occurrence Predefined Type	Common Use Definitions
IfcElement
	Box Geometry	Common Use Definitions
	FootPrint Geometry	Common Use Definitions
	Body SurfaceOrSolidModel Geometry	Common Use Definitions
	Body SurfaceModel Geometry	Common Use Definitions
	Body Tessellation Geometry	Common Use Definitions
	Body Brep Geometry	Common Use Definitions
	Body AdvancedBrep Geometry	Common Use Definitions
	Body CSG Geometry	Common Use Definitions
	Mapped Geometry	Common Use Definitions
	Mesh Geometry	Common Use Definitions
IfcBuildingElement
	Product Assignment	Common Use Definitions
	Surface 3D Geometry	Common Use Definitions
IfcStair
	Object Typing	Common Use Definitions
	Property Sets for Objects	Common Use Definitions
	Material Single	Common Use Definitions
	Spatial Containment	Common Use Definitions
	Element Decomposition	Common Use Definitions
	Product Local Placement	Common Use Definitions
	Axis 2D Geometry	Common Use Definitions
	Body SweptSolid Geometry	Common Use Definitions

Formal representations

XSD Specification

 <xs:element name="IfcStair" type="ifc:IfcStair" substitutionGroup="ifc:IfcBuildingElement" nillable="true"/>

 <xs:complexType name="IfcStair">

  <xs:complexContent>

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

    <xs:attribute name="PredefinedType" type="ifc:IfcStairTypeEnum" use="optional"/>

   </xs:extension>

  </xs:complexContent>

 </xs:complexType>

EXPRESS Specification


ENTITY IfcStair

 SUBTYPE OF (IfcBuildingElement);

  PredefinedType : OPTIONAL IfcStairTypeEnum;

 WHERE

  CorrectPredefinedType : NOT(EXISTS(PredefinedType)) OR
 (PredefinedType <> IfcStairTypeEnum.USERDEFINED) OR
 ((PredefinedType = IfcStairTypeEnum.USERDEFINED) AND EXISTS (SELF\IfcObject.ObjectType));
  CorrectTypeAssigned : (SIZEOF(IsTypedBy) = 0) OR
  ('IFCSHAREDBLDGELEMENTS.IFCSTAIRTYPE' IN TYPEOF(SELF\IfcObject.IsTypedBy[1].RelatingType));
END_ENTITY;

 EXPRESS-G diagram

Link to this page

	Treppe
	Stair
	Escalier

IfcStair

Semantic definitions at the entity

Inherited definitions from supertypes

Definitions applying to Common Use Definitions

Formal representations