IFC vs BCF: what's the difference?

Quick answer: IFC and BCF are not competing formats — IFC carries the building model, BCF carries the issues raised about it. An IFC file holds the geometry and data of walls, ducts and columns, and is typically tens or hundreds of megabytes. A BCF file holds only a comment, a status and a saved camera position pointing at the problem, so it stays small enough to email. Both are open standards published by buildingSMART International, and a normal coordination workflow uses them together.

IFC and BCF are often mentioned in the same conversation, which makes it easy to assume that they are competing formats. They are not. They solve two different problems within the same BIM workflow.

IFC is used to exchange the model. BCF is used to exchange the conversation about that model.

That distinction sounds simple, but it explains why one format cannot replace the other. An IFC file gives the project team something to review. A BCF file helps the team record what was found, where it was found and what should happen next.

What is IFC?

IFC stands for Industry Foundation Classes. It is an open standard for sharing digital information about buildings and infrastructure between different BIM applications, published by buildingSMART International and standardised by ISO — IFC4 as ISO 16739-1:2018, and IFC4.3 as ISO 16739-1:2024.

In everyday work, an IFC file is the transferable version of a model. It can contain the geometry of walls, slabs, beams, ducts or bridge elements, but also information that gives those objects meaning: what they are, how they relate to one another and which properties have been assigned to them.

This is what makes IFC different from a simple 3D export. A three-dimensional shape may show that an object exists, but IFC can also tell the receiving software that the object is a door, a structural column or an air terminal. The model is therefore not only visible; it remains structured and can be reviewed, filtered and checked.

The practical purpose of IFC is interoperability. An architect, structural engineer, MEP designer, contractor and client may all work in different software, yet still need a common version of the project. IFC provides that shared reference without requiring everyone to use the same authoring tool.

Strictly speaking, IFC is more than a file extension: it is a standardised data schema that can be represented in different technical forms. In normal project language, however, “the IFC” usually means the model file issued for exchange or coordination — and that is the meaning most people have in mind when comparing IFC with BCF.

What is BCF?

BCF stands for BIM Collaboration Format. It was created for a different reason: to make communication about a model precise, portable and understandable across software platforms.

Imagine that a reviewer finds a ventilation duct passing through a structural beam. Sending the entire model back with a message such as “please check the clash on level two” leaves plenty of room for confusion. Which view should be opened? Which elements are involved? Is the issue new, resolved or still waiting for a decision?

A BCF issue keeps that context together. It can bring the recipient back to the relevant location in the model, identify the affected objects and carry the comment, status and responsibility associated with the issue. Instead of merely describing where the problem is, BCF helps software show it.

The important point is that BCF does not need to carry the complete BIM model. It refers to the model that the project team already has. This keeps the exchange lightweight and allows coordination comments to move between tools without repeatedly sending large model files.

BCF is therefore closer to a structured issue register than to a design file. It does not describe the whole building or infrastructure asset. It describes what someone wants to discuss, verify, change or approve within that asset.

What is the difference between IFC and BCF?

The clearest way to understand the difference is to look at what would be lost if either format were missing.

Without IFC, the team may have comments but no reliable, software-neutral model to which those comments refer. Without BCF, the team may have the model but no consistent way to exchange the findings made during its review.

An IFC file answers questions such as: What is in the model? Where are the elements? What are they, and what information do they carry?

A BCF issue answers a different set of questions: What requires attention? Where is the issue? Who should respond, and what is its current status?

This is why exporting a new IFC every time someone adds a comment is inefficient. The model and the coordination process develop at different speeds. A design team may issue a new model once a week, while reviewers create, update and close dozens of issues in between. BCF allows that conversation to continue without turning every comment into another full model exchange.

In a typical coordination cycle, the author publishes an IFC model and the reviewer examines it in a model-checking or coordination tool. Any clashes, questions or design concerns are recorded as BCF issues and returned to the responsible team. The designers then update the source model, respond to the issues and publish a revised IFC when the next model exchange is due.

IFC and BCF are therefore not alternatives. They are complementary. IFC is the shared project information; BCF is the structured dialogue that helps the team improve it.

Where Bimlyte fits

The difference between IFC and BCF is clear in theory, but in practice many people do not need a large BIM platform. They simply need to open a model, understand an issue and produce a report that others can use.

Bimlyte brings those tasks together directly in the browser. You can open an IFC model for visual review and work with the coordination issues connected to it. The model provides the project context, while the issues capture the questions, comments and actions that arise during the review.

When the information needs to move to another BIM application, it can be exported as BCF. When it needs to be shared with a client, manager or site team that does not use specialist BIM software, the same information can be turned into a PDF or Excel report.

This matters because good coordination should not depend on everyone having the same software or the same level of BIM experience. IFC keeps the model open, BCF keeps the discussion structured, and Bimlyte makes both easier to access. Files are processed on your device, so project data does not need to be uploaded to a remote server before it can be reviewed.

Browse our guides for step-by-step help using Bimlyte, or open Bimlyte and try it with your own files.