BIM Fit Check, Round 1

Cover image: buildingSMART Deutschland

Štefan Jaud was the Technical Lead for the first BIM Fit Check, held on May 8, 2025 at the 22nd buildingSMART-Anwendertag in Essen. That role starts long before the event: deciding what "correct" actually looks like for georeferencing in IFC, writing the evaluation criteria, and building the test models to showcase the different (even edge) cases that are supported by the specification.

The use case: georeferencing. The question: if an engineering firm designs a bridge in ETRS89/UTM32 (EPSG:25832 horizontal, DHHN2016 / EPSG:7837 vertical) and hands over an IFC file, does the receiving software know where that bridge actually is? The exporting software needs to encode the coordinate reference system correctly using IfcProjectedCRS, IfcMapConversion, and IfcRigidOperation — a combination introduced in IFC 4.3 that many tools still handle inconsistently. The importing software needs to read it back and confirm it. Same scenario, same model, same standard for all six participants.

Defining what correct IFC implementation looks like and checking whether software actually does it is the same work that goes into Jaud IT's infrastructure consulting. The Fit Check just does it in public.

Source: buildingSMART Deutschland — Handout zum ersten BIM FIT CHECK, 8. Mai 2025