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What is an IFC file and why should I care?

IFC is the open format that carries a BIM model between applications — and between decades. If a model only opens in the application that created it, it is not an archive; it is a hostage.

In one sentence: IFC (Industry Foundation Classes) is the open data format for exchanging BIM models between applications and organisations — standardised as ISO 16739-1 and maintained by buildingSMART International. The current version is IFC 4.3, and it is the only common language that Revit, ArchiCAD, FreeCAD, Tekla and a dozen viewers all understand.

standardISO 16739-1 IFC 4.3 is current
format cost€0 public specification
opens inany BIM and in a text editor
mentions in Portuguese competitions (2010–2026)0 / 1,059 measured

1 · How a model reaches IFC

The path from authoring to archive has four stations. The word most people are missing is MVD — the subset of the schema each delivery uses.

Authoring Export .ifc file Reader Revit · ArchiCAD FreeCAD · Bonsai via MVD (the right subset for the delivery) open text, ISO 16739-1 viewer, checking, archive THE SAME FILE OPENS IN ANY TOOL — TODAY AND IN 20 YEARS
Authoring → export (MVD) → IFC file → reading. Each arrow is a conversion with no contract loss: IFC is the meeting point.

Three things in this diagram matter to whoever is buying:

2 · Why should I care

For the archive, not for the day to day. Day to day, everyone works in the native format of their own tool. IFC enters at the moments when information changes hands: delivery to the client, coordination between disciplines, building permitting, the building’s archive — and, more and more, in the EU digital product passport, where product data travel in open formats (study published on this site).

A model delivered only in native format is an asset that rots at the speed of the software versions that read it. An IFC kept alongside it is the project’s life insurance: neutral, auditable, independent of the vendor. It is also the format that public procurement in the countries that require BIM requires — and the reason why the Portuguese state, once Decree-Law 10/2024 (DL) enters into force (BIM mandatory in building permitting from 2030), will hardly be able to accept proprietary formats alone.

3 · And in Portugal?

Almost nobody asks for IFC yet — 0 mentions in 1,059 architecture competition documents (2010–2026) read in full (meta-concurso [measured]). But the legal framework already admits models: the Ministerial Order 255/2023 (Portaria), which governs detailed design in public works, accepts BIM models as submission documents (DR), and DL 10/2024, art. 17 makes BIM mandatory in urban building permitting from 1 January 2030 (DR). Delivering and asking for IFC today is the cheap way to be ready for that day.

4 · Frequently asked questions

What is an IFC file, in simple words?

A text file that describes an entire building — elements, materials, properties, relationships — in a public format standardised by ISO (16739-1). Any serious BIM tool reads and writes it.

Is IFC free? Do I lose anything by delivering in IFC?

The format is free, with no licences. You lose modelling parametrics and some sheet graphics; you gain longevity and interoperability. Current practice is IFC as the delivery format, natives kept by whoever models.

Which version should I use?

IFC4 for new buildings; IFC 4.3 when there is infrastructure or product data requirements. IFC 2x3 only when the recipient imposes it out of inertia.

How can I see what is inside an IFC without buying software?

Open it in a text editor — it is text. To see the model and the product data, the readiness meter on this site loads IFC in the browser, with no upload: the file never leaves your computer.

In Portugal, will anyone require IFC of me?

Today, almost nobody (0/1,059 in measured competitions). The legal framework (Ministerial Order 255/2023, DL 10/2024) already points that way; when the obligation arrives, open formats are the only way for the state not to end up captive to a vendor.

5 · The next step

Load an IFC and see what it really contains

The digital product passport readiness meter opens an IFC in the browser — geometry, identifiers, properties, classification — and tells you how far the product data are from what the EU digital product passport will require. No upload, no installation.

Open the meter