If you already do this for a living: The export settings, not the model. Most IFC problems (proxies, missing properties, wrong storeys) come from one export setting and are fixed once, not element by element.
- Watch out
- What it costs
- Experienced readers
- Remember
- In BIMpedia
The MEP model is exported with default settings and shared on Friday. On Monday the federated model shows 2,000 proxies, every duct on level 0, and no system names. The coordination round is postponed a week.
The MEP modeller opens the export in the IFC Inspector before sharing: proxies 2,014, storeys 1. Fixing the export mapping takes twenty minutes, and Monday’s round runs on a clean model.
An IFC export can look fine in its authoring tool and still cause trouble everywhere else. A short routine before every share catches most problems.
- 1HeaderSchema, application, view
- 2Spatial structureStoreys and containment
- 3ClassesProxies, names, duplicates
1. Read the header
The file header tells you the schema (IFC2X3, IFC4 or IFC4X3), the application that exported it and the view definition it targets. If the BEP asks for IFC4 Reference View and you receive IFC2X3 Coordination View, stop there and ask for a new export.
2. Check the spatial structure
Every IFC model has a tree: project, site, building, storeys (or, for infrastructure, facilities and their parts). Check that:
- the storeys you expect are all there, with sensible names and elevations
- elements are contained in those storeys — elements outside the structure are easy to miss in every downstream tool
3. Look for mapping problems
A few quick counts reveal most export problems:
- Proxies (
IfcBuildingElementProxy) — objects the exporter did not know how to classify. A few are normal; hundreds are not. - Unnamed elements — hard to find, filter and discuss.
- Duplicate GlobalIds — they break issue tracking with BCF and change detection between versions.
4. Check the information, not just the geometry
Open a few elements and look at their property sets. Then check the properties your project actually requires — fire ratings on doors and walls, manufacturer data on plant, classification codes. The list should come from the information requirements or the LOD/LOIN matrix, and can be written as an IDS file for automatic checking.
5. Record what you found
Note the result in the coordination meeting or the issue log, and send the report to the task team that produced the file. Over a few weeks, exports get noticeably better.
Key takeaways
- Check the header: schema version, exporting application and view definition.
- Check the spatial structure: project, site, building and the expected storeys, with elements assigned to them.
- Watch for proxies, unnamed elements and elements outside the spatial structure — they usually point to export mapping problems.
- Check that required properties are present and filled, ideally against an agreed list or IDS file.
Your notesSaved locally
Related tool
Open an IFC file in the browser: structure, elements, properties and required-property checks.
Open IFC Inspector →