The Building Information Modeling (BIM) industry includes professionals that specialize in various types of work, for example, architects, thermal engineers, road/railroad designers, etc. This work requires specialized software tools, and each software product has its own internal model representing a place or a process, for example, a building or its construction process. This means that the software tools use different internal data schemas that are not compatible with each other.
Collaboration and coordination between specialists is an important part of the work, and data should be exchanged between various software tools. One way to communicate between software tools is to design a large number of import and export plug-ins or modules, but this is not practical due to changes introduced to the internal data models of each tool for each release. Also this approach is not ideal because you need dedicated import and export functionality for each tool with which you want to collaborate.
Industry Foundation Classes (IFC) offers clear interoperability and organization between companies, software systems, data formats, and specialists within a shared project.
IFC is an open, platform-neutral standardized format for the unified exchange of digital information for the construction of buildings, products, and other kinds of assets. IFC provides a transparent way to represent project data independently from the hardware, platforms, formats, and software used by various specialists involved in a project at all stages of its life cycle. IFC guarantees the integrity and consistency of data and provides standard interfaces for interoperability.
At the logical layer, IFC is based on a schema definition. The schema represents an information model that includes the formalized description of the following:
- Objects (entities) — Entities are identified with a unique identifier (for most objects), name and type.
- Attributes of objects — Meaningful characteristics of entities.
- Relationships — Processes between objects that are related to entities within the project.
- Non-construction indicators — Important non-construction details for the project (economic, performance, etc.).
- Actors — Specialists who communicate while the project is being realized.
For more details about schemas, see IFC Schemas.
At the physical layer, IFC data can be represented in various file formats. See IFC Formats for the full list of IFC data formats supported by ODA.
The interoperability process based on IFC does not assume that you apply changes in the IFC representation, although it is possible to change data in an IFC file. A more convenient way to change data is to request changes from the author of the original CAD model. After edits are completed, the author converts the data into IFC format and sends the modified data back to the collaborator who requested the changes.
The IFC data structure is defined with the EXPRESS descriptive language (data definition language). This language is not a programming language and is independent of any programming implementations. Every entity in IFC has a definition, which makes IFC a semantic standard.
Data manipulation operation requirements and specifications are described in the Standard Data Access Interface (SDAI).
Other benefits of using IFC:
- IFC has a well developed data model for buildings and architecture. It is a standard for many BIM-related companies worldwide.
- IFC is used in a constantly growing number of applications.
- The IFC data model standard is active and developing for the most recent needs and challenges.
ODA IFC SDK implements functionality for working with the IFC open data format, which is widely used in BIM and facility management industries.
IFC is developed and maintained by buildingSMART International. The IFC data format is described in the international standard ISO 16739.