Defined in File Ifc4x3_rc1.h
IfcZone: public Ifc4x3_rc1::IfcSystem¶
Definition from IAI: A zone isa 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 IfcGroup. NOTE Certain use cases may restrict the freedom of non hierarchical relationships. In some building service use cases the zone denotes aview based delimited volume for the purpose of analysis and calculation. This type of zone cannot overlap with respect to that analysis, but may overlap otherwise. 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 used. RECOMMENDATION 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 RunningDuct
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. HISTORY New entity in IFC Release 1.0 IFC2x4 CHANGE The entity is now subtyped from IfcSystem (not its supertype IfcGroup) with upward compatibility for file based exchange. Property Set Use Definition: The property sets relating to the IfcZone are defined by the IfcPropertySet and attached by the IfcRelDefinesByProperties relationship. It is accessible by the inverse IsDefinedBy relationship. The following property set definitions specific to the IfcZone are part of this IFC release:
Pset_ZoneCommon: common property set for all types of zone Pset_SpaceFireSafetyRequirements: common property set for all types of zones to capture the fire safety requirements Pset_SpaceLightingRequirements: common property set for all types of zones to capture the lighting requirements Pset_SpaceOccupancyRequirements: common property set for all types of zones to capture the occupancy requirements Pset_SpaceThermalRequirements: common property set for all types of zones to capture the thermal requirements
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.
IFC2x4 CHANGE The attribute has been added at the end of the entity definition.