A zone is a group of spaces,
partial spaces or other zones. Zone structures may not be
hierarchical (in contrary to the spatial structure of a project -
see IfcSpatialStructureElement), i.e. one individual
IfcSpace may be associated with zero, one, or several
IfcZone's. IfcSpace's are grouped into an
IfcZone by using the objectified relationship
IfcRelAssignsToGroup as specified at the supertype
NOTE Certain use cases may restrict the
freedom of non hierarchical relationships. In some building
service use cases the zone denotes a view based delimited volume
for the purpose of analysis and calculation. This type of zone
cannot overlap with respect to that analysis, but may overlap
HISTORY New entity in IFC1.0
IFC4 CHANGE The entity is now subtyped from IfcSystem (not its supertype IfcGroup) with upward compatibility for file based
Common Use Definitions
The following concepts are inherited at supertypes:
The Object Classification concept applies to this entity.
Additional classifications of the IfcZone, as provided
by a national classification system, can be assigned by using the
IfcRelAssociatesClassification relationship, accessible
via the inverse attribute HasAssociations. The
IfcZone can be assigned to a spatial structure element, it
refers to, e.g. to a particular IfcBuildingStorey by using
the IfcRelServicesBuildings relationship, accessible via
the inverse attribute ServicesBuilding.
Property Sets for Objects
The Property Sets for Objects concept applies to this entity as shown in Table 78.
Table 78 — IfcZone Property Sets for Objects
The Group Assignment concept applies to this entity as shown in Table 79.
Table 79 — IfcZone Group Assignment
An IfcZone is a spatial system under which individual
IfcSpace's (and other IfcZone's) are grouped. In
contrary to the IfcSpatialZone entity, IfcZone is a
mere grouping, it can not define an own geometric representation
and placement. Therefore it cannot be used for spatial zones
having a different shape and size compared to the shape and size
of aggregated spaces.
NOTE The IfcZone is regarded as the
spatial system (as compared to the building service, electrical,
or analytical system), the name remains IfcZone for
compatibility reasons, instead of using a proper naming
convention, like IfcSpatialSystem.
NOTE One of the purposes of a zone is to
define a fire compartmentation. In this case it defines the
geometric information about the fire compartment (through the
contained spaces) and information, whether this compartment is
ventilated or sprinkler protected. In addition the fire risk code
and the hazard type can be added, the coding is normally defined
within a national fire regulation. All that information is
available within the relevant property sets. Again, if an
independent shape has to be provided to the fire compartment,
then the entity IfcSpatialZone shall be
In case of a zone denoting a (fire) compartment, the following types should be used, if
applicable, as values of the ObjectType attribute:
- 'FireCompartment': a zone of spaces, collected to represent a single fire compartment.
- 'ElevatorShaft': a collection of spaces within an elevator, potentially going through many storeys.
- 'RisingDuct': A collection of vertical airspaces.
- 'RunningDuct': A collection of horizontal airspaces.
XSD Specification: <xs:element name="IfcZone" type="ifc:IfcZone" substitutionGroup="ifc:IfcSystem" nillable="true"/>
<xs:attribute name="LongName" type="ifc:IfcLabel" use="optional"/>
|WR1|| : ||(SIZEOF(SELF\IfcGroup.IsGroupedBy) = 0) OR
(SIZEOF (QUERY (temp <* SELF\IfcGroup.IsGroupedBy.RelatedObjects |
NOT(('IFCPRODUCTEXTENSION.IFCZONE' IN TYPEOF(temp)) OR
('IFCPRODUCTEXTENSION.IFCSPACE' IN TYPEOF(temp)) OR
('IFCPRODUCTEXTENSION.IFCSPATIALZONE' IN TYPEOF(temp))
))) = 0);|
|LongName|| : ||
Long name for a zone, 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 zone, and the LongName refers to the full name.
IFC4 CHANGE The attribute has been added at the end of the entity definition.
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