Provision of a spatial structure of the project by aggregating spatial structure elements. The spatial structure is a hierarchical tree of spatial structure elements (site, building, storey, space) ultimately assigned to the project. Composition refers to the relationship to a higher level element (e.g. this storey is part of a building).
The order of spatial structure elements being included in the concept are from high to low level: IfcProject, IfcSite, IfcBuilding, IfcBuildingStorey, IfcSpace. Therefore an spatial structure element can only be part of an element at the same or higher level.
Figure 17 illustrates an instance diagram.
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Figure 17 — Spatial Composition |
This concept is used by entities for exchanges as shown.
IfcBuilding | R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
IfcBuildingStorey | O O |
O O |
O O |
O R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
IfcSite | R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
IfcSpace | O O |
O O |
O O |
O R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |
R R |