IFC Explained: The Open Format That Keeps Architects, Engineers & Contractors Aligned

Let's be honest — construction projects are messy. The architect models the building in one software, the structural engineer works in another, the MEP team has their own tools, and somewhere along the way someone is emailing PDFs and hoping for the best. Sound familiar?

That's the problem IFC was designed to solve. And if you work in BIM, it's worth understanding what it actually is — not just "the format we export to" but why it exists and what it does for your workflow.

So, what is IFC exactly?

IFC stands for Industry Foundation Classes. It's an open, neutral file format for sharing building and construction data between different software applications. Think of it as the universal language of BIM — a way for ArCADia, Revit, ArchiCAD, Allplan, and dozens of other tools to pass a model back and forth without losing the important stuff.

Unlike a DWG file — which is essentially a drawing — an IFC file carries structured information. Walls know they are walls. Doors know which wall they belong to, which floor they're on, and what their fire rating is. That's a fundamentally different kind of data, and it's what makes multi-discipline collaboration possible without someone having to manually re-enter everything from scratch.

IFC is maintained by buildingSMART International, a neutral non-profit organisation, which means no single software vendor owns or controls it. The current widely-used version is IFC4, and it's the backbone of the ISO 19650 standard that European governments are increasingly building their BIM mandates around.

Why does it matter on a real project?

Picture a mid-sized commercial building project. The architect finishes the schematic design in ArCADia BIM and exports an IFC file. The structural engineer opens it in their calculation software, positions their beams and columns relative to the architectural model, and sends back their own IFC. The MEP team does the same for the duct runs and pipework. Everyone is working from a shared reference — not from a PDF, not from a phone call, not from guesswork.

Without IFC, coordination means endless emails, version confusion, and someone discovering a clash between a structural beam and an HVAC duct during construction — not during design.

With IFC, clash detection can happen at the model level, before a single thing is built. Software can automatically flag where a pipe intersects a wall that wasn't supposed to have an opening, or where a column lands in the middle of a doorway. Catching those things in a model is cheap. Catching them on site is not.

What actually gets saved in an IFC file?

Quite a lot, as it turns out. An IFC file can contain:

Geometry — the 3D shapes of building elements
Object classification — walls, slabs, beams, windows, doors, spaces, systems
Properties — materials, fire ratings, thermal performance, load-bearing status
Relationships — which elements are part of which storey, which system, which zone
Project metadata — site location, client, author, software used

This is why IFC is so much more useful than exporting a 3D DXF or a PDF. The geometry is there, but so is the meaning behind the geometry. A downstream application can query the model intelligently — "show me all fire doors on the second floor" or "what is the total external wall area" — rather than just displaying shapes.

Open format — why does that matter?

It matters more than it might seem. BIM workflows in real European practice involve firms using different software on different budgets. A large architectural practice might use Revit. A small engineering consultancy might use ArCADia or Tekla. A contractor might use something else entirely. If the format was proprietary — owned by one vendor — collaboration would mean everyone buying the same software. That's great for the software vendor and painful for everyone else.

IFC being open means any software that supports it can participate in the workflow on equal terms. It's one of the reasons smaller and mid-market BIM tools can compete with the Autodesk ecosystem — because the playing field for data exchange is level.

A few things IFC isn't (yet)

IFC is genuinely useful but it's not magic. A few honest caveats:

Round-tripping is imperfect. Export a model to IFC, import it in another tool, and you may lose some parametric relationships. The geometry is usually fine; the intelligence behind it varies.
Not all software implements IFC equally well. A "supports IFC" label on a product can mean anything from excellent to barely functional. It's worth testing your specific software combination.
IFC is a snapshot, not a live link. When you export an IFC, you're capturing the model at that moment. Changes made afterward need a new export. Proper workflow discipline around versioning matters.

None of these are dealbreakers — they're just things to know going in so you can manage your process accordingly.

IFC and ArCADia BIM

ArCADia BIM 14 supports IFC import and export as a core feature, not an add-on. That means you can bring in an IFC model from another platform as a reference layer, build your own elements on top of it, run collision checks against it, and export your work back out as IFC for other teams to use.

In practice, this is increasingly important. Public tenders in Germany, the UK, Italy, and other European markets are specifying IFC deliverables as a requirement. Having a tool that handles this natively — rather than through a clunky third-party plugin — makes a genuine difference when you're managing deadlines.

The bottom line

IFC isn't glamorous. It's a file format. But it's the file format that makes the whole idea of Building Information Modeling actually work across team boundaries — and in a world where construction projects involve more disciplines, more consultants, and more regulatory requirements than ever, that's not a small thing.

If you've been treating IFC as just "the thing you export at the end", it might be worth spending an afternoon digging into what's actually in those files and how your workflow could use that data more deliberately. You might be surprised how much time it saves.

IFC Explained.How one open format keeps architects, engineers and contractors actually talking to each other