Write down the reference before moving the model
Request the survey's coordinate information and control record. Identify the horizontal coordinate reference system, the vertical reference, and the units. Clarify the difference between a model level named zero and a surveyed elevation. Similar-looking coordinate values do not establish that two datasets use the same reference.
Create a project coordinate note that a new team member can follow. Include the source of the reference, relevant identifiers, orientation convention, and responsible reviewer. Where information is missing, resolve it with the survey team rather than substituting a familiar national or local system.
Define the relationship between local and map coordinates
A model may use a convenient local origin while retaining a defined relationship to map coordinates. buildingSMART's georeferencing guidance describes this approach and its value when working with large map coordinates. The project must preserve that relationship instead of repeatedly moving exported geometry by eye.
IFC's IfcMapConversion describes a conversion from local engineering coordinates to a projected map reference using translation, orientation, and scale information. It does not itself perform the geodetic map projection. Have the appropriate specialist resolve transformations when source datasets use different reference systems or when site extent requires particular treatment.
Coordinate the authoring tools
Choose an authoritative coordinate source and test the procedure in the software versions used by the project. Revit's shared coordinates establish relationships between linked files, but the setup still needs to reflect the approved survey reference. Record the procedure and protect the resulting relationship from casual editing.
Differentiate project orientation from the north direction used by the survey or map. Check how each application handles these settings on import and export. A model can appear correctly oriented on a sheet while carrying a different spatial relationship in an exchange file.
Verify location through independent references
Use several well-distributed references to test the assembled data, including elevation. Check a point near the chosen origin and others farther away. A single matching location can fail to expose an incorrect rotation or scale. Select identifiable references whose coordinates are supported by the survey record.
Repeat the check in the receiving application after export. Confirm that the intended coordinate metadata is present and interpreted correctly. Keep the check results and file revisions together. A successful view inside the authoring application is evidence of that setup, not proof that every later exchange preserves it.
Keep the integration maintainable
Deliver a coordinate note, reference-point information, transformation record, and tested exchange files with the model. State which file defines the approved relationship and how a recipient can verify it. Include any software-specific limitations discovered during the exchange test.
Treat a coordinate change as a project change affecting linked information. Assess its impact on civil data, point clouds, discipline models, and issued outputs before implementing it. For multiple buildings or an extensive site, plan the relationship among model areas deliberately instead of assuming that one convenient local setup suits every asset.
Common questions
Is a latitude and longitude enough to georeference a BIM model?
A location alone does not fully describe a model's orientation, elevation basis, units, or relationship to survey control. The project needs a complete, tested positioning agreement appropriate to its exchange workflow.
Why can models align at one point but diverge elsewhere?
Possible causes include different orientations, scale, units, or coordinate references. Check the documented setup and multiple references before making a local adjustment that could conceal the underlying problem.
Further reading
This article was rewritten in October 2026 around the subject of the original Geobiro post. The original publication date is retained; the update date identifies the current text.