Coordination of models in IFC

The geographic coordinates determine a location system, structured by invisible lines drawn in parallel, and the combination of these lines creates addresses and levels.

When carrying out a project with the BIM methodology, the BIM modeler must determine the geographic coordinates for the model, in order to orient itself in the three-dimensional Cartesian space.

However, a subdivision has its geographic information, so the projected building will be positioned relative to the origin of the land, and from that a hierarchy follows in the elaboration of the model, where the levels are assigned to the building reference, and the objects relatively to the floors. Therefore, the system in .ifc format uses its coordinates from this concept.

For Revit software users who export models to .ifc format, they have the option of choosing the orientation of the model's coordinates, either by Internal Coordinates, Project Base Point, Land Survey Point or Shared Coordinates.

However, for the reverse of this, the import of models in .ifc format for the Revit software, it is based only on Internal Coordinates. Therefore, it is advisable to export the .ifc models always considering the internal origin as the coordination of the model, so that there are no differences depending on the type of file.

Coordinate Points:

Internal Coordinate

Project Base Point

Land Topographic Survey Point