What IFC actually is
IFC is an open data standard for exchanging building and infrastructure information between software applications. An IFC file is not simply a frozen 3D model. It can carry objects, relationships, classifications, materials, properties, quantities, systems and spatial placement.
The five things to inspect first
- Project and spatial tree: project, site, building, storeys and spaces should form a sensible hierarchy.
- Object class: a wall should normally be an
IfcWall, a door anIfcDoor, and a space anIfcSpace. Generic proxies deserve investigation. - Name and type: identify the individual object and the reusable type without mixing the two.
- Property sets: check whether agreed properties exist, use the correct names and contain usable values.
- Placement: confirm storey elevation, local origin, orientation and shared coordinates before combining disciplines.
Choose the delivery, not the newest label
| Choice | Use it when | Watch for |
|---|---|---|
| IFC 2x3 | A contract, client system or older coordination tool explicitly requires it. | Older workflows may map modern objects and properties less precisely. |
| IFC 4 | The project and receiving tools support a modern building exchange. | Confirm the required Model View Definition and software certification. |
| IFC 4.3 | Infrastructure scope or a project requirement specifically calls for it. | Implementation support varies; test the receiving workflow early. |
The correct version is the one agreed by the project and supported by the receiving workflow. Do not silently change schema or export view shortly before delivery.
A 15-minute first-model check
- Keep the native file and original export untouched.
- Open the IFC in a viewer that is not the authoring application.
- Check model extents and coordinates before zooming into objects.
- Expand the spatial tree and confirm storeys and spaces.
- Select one wall, door, slab, space and system object.
- Compare class, name, type and required properties with the delivery requirement.
- Hide and isolate disciplines to look for duplicates and unexpected proxies.
- Record the exporter name, schema, export view and time.
Beginner mistakes that cost time
Opening the IFC only in the software that created it can hide exchange problems. Visual appearance alone also proves very little: a model can look correct while object classes, properties or coordinates are unusable. Finally, do not treat every warning as equal. Prioritize requirements that affect coordination, quantity use, handover or automated checks.
What to learn next
Once the first model is readable, move from visual inspection to explicit information requirements. IDS can describe which IFC objects and alphanumeric information must be present, making repeated checks less dependent on memory.