IFC and openBIM

Industry Foundation Classes is an open data schema for built-asset information, maintained by buildingSMART International and published as ISO 16739. An IFC file describes objects (IfcWall, IfcDoor, IfcSpace), their properties, relationships and geometry in a vendor-neutral way. openBIM is the approach of collaborating through open standards like IFC and BCF.

Common versions are IFC2x3 and IFC4 (with IFC4.3 adding infrastructure such as roads, rail and bridges). A Model View Definition (MVD) or view defines which part of the schema an exchange uses — for example a coordination view for clash detection or a reference view for simple viewing. The project's EIR/BEP should state the version and view required.

The BIM Collaboration Format exchanges issues — a viewpoint, a snapshot, comments and status — between tools, without sending whole models. A coordinator raises a BCF topic in a checking tool; the designer opens it in their authoring tool at the exact location.

IFC is a reference exchange: re-importing IFC into an authoring tool rarely gives fully editable native objects. Geometry can be heavy if complex families export as meshes. Property names must be agreed. Always check the exported file, not just the export settings.