According to the UK BIM Task Group (Bew and Richards, 2008), there are four BIM maturity levels.
Based on 2D CAD and the exchange of paper-based drawings.
Partial 3D modeling of the facility (mostly for complex geometries) while most of the design is still realized by means of 2D drawings.
Data exchange is realized through sending and receiving individual files, and a central project platform is not employed.
Defined by the use of BIM software products for authoring digital building models, however, each of the various disciplines involved develops its own model.
Their mutual consistency is ensured by periodic coordination sessions, where the individual sub-models are brought together and checked for clashes or other discrepancies.
2D drawings are mostly derived from BIM models.
Data exchange is still realized on the basis of files (in native formats), however, all files are managed on a central platform.
For handing over BIM models comprising both 3D geometry and semantics, open standards are not demanded on BIM Level 2. Instead, proprietary formats may be used.
Based on the concept of a fully integrated BIM.
It is based on the implementation of BIG Open BIM, i.e. ISO standards are employed for data exchange and process descriptions, and deeply integrated digital models are used throughout the entire lifecycle.
Cloud services are used for managing project data so that data is continuously and consistently maintained over the building’s life cycle.