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A building represents a structure that provides shelter for its occupants or contents and stands in one place. The building is also used to provide a basic element within the spatial structure hierarchy for the components of a building project (together with site, storey, and space).NOTE Definition from ISO 6707-1: Construction work that has the provision of shelter for its occupants or contents as one of its main purpose and is normally designed to stand permanently in one place.A building is (if specified) associated to a site. A building may span over several connected or disconnected buildings. Therefore building complex provides for a collection of buildings included in a site. A building can also be decomposed in (vertical) parts, where each part defines a building section. This is defined by the composition type attribute of the supertype IfcSpatialStructureElements which is interpreted as follow:COMPLEX: building complex ELEMENT: building PARTIAL: building sectionThe IfcBuilding is used to build the spatial structure of a building (that serves as the primary project breakdown and is required to be hierarchical). The spatial structure elements are linked together by using the objectified relationship IfcRelAggregates. Figure 1 shows the IfcBuilding as part of the spatial structure. It also serves as the spatial container for building and other elements.NOTE Detailed requirements on mandatory element containment and placement structure relationships are given in model view definitions.Figure 1 — Building compositionSystems, such as building service or electrical distribution systems, zonal systems, or structural analysis systems, relate to IfcBuilding by using the objectified relationship IfcRelServicesBuildings.Figure 2 describes the heights and elevations of the IfcBuilding. It is used to provide the height above sea level of the project height datum for this building, that is, the internal height 0.00. The height 0.00 is often used as a building internal reference height and equal to the floor finish level of the ground height of building, also referred to as ridge height (top of roof structure, e.g the ridge against terrain): provided by Qto_BuildingBaseQuantities with Name="Height" eaves height of building (base of roof structure, e.g the eaves against terrain): provided by Qto_BuildingBaseQuantities with Name="EavesHeight"Figure 2 — Building elevationsHISTORY New entity in IFC1.0.

A curtain wall is a wall of a building which is an assembly of components, hung from the edge of the floor/roof structure rather than bearing on a floor. Curtain wall is represented as a building element assembly and implemented as a subtype of IfcBuildingElement that uses an IfcRelAggregates relationship. A curtain wall is often external, but using Pset_CurtainWallCommon.IsExternal can be used to define interior curtain walls.{ .extDef}NOTE Definition according to ISO 6707-1: non load bearing wall positioned on the outside of a building and enclosing it. HISTORY New entity in IFC2.0The geometric representation of IfcCurtainWall is given by the IfcProductDefinitionShape, allowing multiple geometric representations. Independent 'Body' geometric representation, as described below, should only be used when the IfcCurtainWall is not defined as an aggregate. If defined as an aggregate, the geometric representation is the sum of the representations of the components within the aggregate.The geometric representation of IfcCurtainWall is defined using the following multiple shape representations for its definition:Axis: A two-dimensional open curve (for restrictions see below) defining the axis for the curtain wall. This is an optional representation for curtain walls. Body: A surface model or boundary representation model representation defining the 3D shape of the curtain wall. If the IfcCurtainWall has components (referenced by SELF\IfcObject.IsDecomposedBy) then no independent shape representation with RepresentationType = 'Body' shall be defined. The body of IfcCurtainWall is then geometrically represented by the shape representation of its components. The components are accessed via SELF\IfcObject.IsDecomposedBy[1].RelatedObjects. If the IfcCurtainWall has no components defined (empty set of SELF\IfcObject.IsDecomposedBy) then the IfcCurtainWall may be represented by an shape representation with the RepresentationIdentifier ='Body'.

The door is a built element that is predominately used to provide controlled access for people, goods, animals and vehicles. It includes constructions with hinged, pivoted, sliding, and additionally revolving and folding operations. A door can:be a "free standing" door, contained in an IfcSpatialElement such as an IfcBuildingStorey. fill an opening, typically in a wall. The door will then have a FillsVoids attribute which uses the IfcRelFillsElement relationship to relate the IfcDoor with the IfcOpeningElement; be part of an element assembly, typically an IfcCurtainWall. The door will then have a Decomposes attribute which uses the the IfcRelAggregates relationship to relate the door with the assembly of elements;There are two main representations for door occurrences:IfcDoor entities that have a 3D rectangle 'Profile' shape representation defined. This profile can then be used to parametrically generate the geometry of a door. If not provided, the profile of the IfcOpeningElement can be used if the door fills an opening. The parameters are specified on the relating IfcDoorType that references IfcDoorLiningProperties and IfcDoorPanelProperties for each panel in the door; IfcDoor entities that are not parametrically generated and have only 'Brep', or 'SurfaceModel' geometry.In addition, an IfcDoor may commonly include a 'FootPrint' representation defining the 2D shape of the door and its swing.The parameters of a door are defined by both the IfcDoor occurence and its IfcDoorType. The IfcDoor specifies:the door width and height the door opening direction (by the positive y-axis of the ObjectPlacement)The IfcDoorType specifies parameters which are common to all of its occurrences of IfcDoor:the operation type (single swing, double swing, revolving, etc.) the door hinge side (by using two different styles for right and left opening doors) the particular attributes for the lining by the IfcDoorLiningProperties the particular attributes for the panels by the IfcDoorPanelPropertiesREFERENCE Definition according to ISO 6707-1: construction for closing an opening, intended primarily for access with hinged, pivoted or sliding operation. NOTE The entity IfcDoorStandardCase has been deleted. Use an IfcDoor with a 'Profile' representation instead. The IfcDoor should also have an IfcDoorType with ParameterTakesPrecedence set to 'TRUE'. HISTORY New entity in IFC1.0.

IfcFacilityPart provides for spatial breakdown of built facilities. It may be further specialised according to the type of facility being broken down.

A footing is a part of the foundation of a structure that spreads and transmits the load to the soil. A footing is also characterized as shallow foundation, where the loads are transferred to the ground near the surface.{ .extDef}NOTE Definition according to ISO 6707-1: stepped construction that spreads the load at the foot of a wall or column. HISTORY New entity in IFC2x2. NOTE Slab foundations, also called slab-on-grade, are not instantiated as IfcFooting but as IfcSlab with a predefined type of IfcSlabTypeEnum.BASESLAB. Deep foundations, which transfer the loads to subsurface layers, are represented by IfcDeepFoundation and its subtypes IfcCaissonFoundation and IfcPile.

A junction box is an enclosure within which cables are connected.Cables may be members of an electrical circuit (for electrical power systems) or be information carriers (in a telecommunications system). A junction box is typically intended to conceal a cable junction from sight, eliminate tampering or provide a safe place for electrical connection.HISTORY New entity in IFC4{ .note}

A border of stone, concrete or other rigid material formed at the edge of the carriageway or footway.NOTE Definition from ISO 6707-1: border, usually upstanding, at the edge of a carriageway, hard strip, hard shoulder, or footway, (Curb, US). NOTE Definition from PIARC: Unit intended to separate surfacings of different surfaces and to provide physical delineation or containment [CEN].

A marine facility represents any major structure or entity that is specific to the ports and waterways domain. examples of this include quays, jetties, shipyards, breakwaters etc.

The opening element stands for opening, recess or chase, all reflecting voids. It represents a void within any element that has physical manifestation. Openings can be inserted into walls, slabs, beams, columns, or other elements.There are two different types of opening elements. The attribute PredefinedType should be used to capture the differences:an opening, where the thickness of the opening is greater or equal to the thickness of the element — the attribute PredefinedType is set to OPENING a recess or niche, where the thickness of the recess is smaller than the thickness of the element — the attribute PredefinedType is set to RECESS for a recess or niche.If the value for PredefinedType is omitted, or the value is set to NOTDEFINED, no specific information of whether it is an opening or recess shall be assumed.An IfcOpeningElement has to be inserted into an IfcElement by using the IfcRelVoidsElement relationship. It may be filled by an IfcDoor, IfcWindow, or another filling element by using the relationship IfcRelFillsElements. Depending on the type of the IfcShapeRepresentation of the IfcOpeningElement the voiding relationship implies:if the IfcShapeRepresentation.RepresentationIdentifier = 'Body', then the Body shape representation of the opening has to be subtracted from the body shape representation of the voided element - implicit Boolean difference operation. if the IfcShapeRepresentation.RepresentationIdentifier = 'Reference', then the Reference shape representation of the opening is not subtracted, it is provided in addition to the hole in the Body shape representation of the voided element.The IfcOpeningElement shall not participate in the containment relationship, i.e. it is not linked directly to the spatial structure of the project. It has a mandatory VoidsElements inverse relationship pointing to the IfcElement that is contained in the spatial structure. The inverse relationship ContainedInStructure shall be NIL.REFERENCE Definition according to ISO 6707-1: void in a building element NOTE The entity IfcOpeningStandardCase has been deleted. Use an IfcOpeningElement with a single extrusion body perpendicular to the wall or slab instead. NOTE See IfcRelVoidsElement for a diagram on how to apply spatial containment and the voiding relationship. IFC2x CHANGE The intermediate ABSTRACT supertypes IfcFeatureElement and IfcFeatureSubtraction have been added. IFC4 CHANGE The attribute PredefinedType has been added at the end of attribute list. HISTORY New entity in IFC1.0

The railing is a frame assembly adjacent to human or vehicle circulation spaces and at some space boundaries where it is used in lieu of walls or to complement walls. Designed as an optional physical support, or to prevent injury or damage, either by falling or collision.HISTORY New entity in IFC2.0

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Classifications of other domains

space access object for upright passage by persons

closure object in a door

access restricting object by a horizontal elongated barrier with a vertical extent

assembly system forming separation towards underground

structural system connecting a construction entity with the underground

Show all classifications of other domains (13) »