Federated building information model
In the UK, the Government Construction Strategy published in May 2011, stated that the '...Government will require fully collaborative 3D BIM (with all project and asset information, documentation and data being electronic) as a minimum by 2016'. This represents a minimum requirement for Level 2 BIM on centrally-procured public projects.
Level 2 is the creation of a managed 3D environment with data attached, but created in separate, distinct discipline models. These separate models may originate with the client, architect, structural engineer, building services engineer, contractor, sub-contractors, suppliers and so on.
The term 'federation' refers to a group of systems and networks operating in a standard, collective and connected environment. A federated building information model is an assembly of distinct discipline models to create a single, complete model of the building.
The AGC ConcensusDocs 301- BIM Addendum, defines a federated model as: '…a model consisting of linked but distinct component models, drawings derived from the models, texts, and other data sources that do not lose their identity or integrity by being so linked, so that a change to one component model in a federated model does not create a change in another component model in that federated model.'
A single federated model is useful for design co-ordination, clash avoidance and clash detection, approvals processes, design development, estimating and so on, but the individual models do not interact, they have clear authorship and remain separate. This means that the liabilities of the originators of the separate models are not changed by their incorporation into the federated model.
Generally, a licence is granted to the client to use the information contained in the separate models for the 'permitted purpose' (ie for the purpose for which that level of detail of information was intended). A sub-license from the client enables project team members to use models prepared by other project team members.
The CIC BIM Protocol requires that the client appoints an information manager. A key role of the information manager is facilitating the management of the federated model. They are essentially a procedural gate-keeper, policing the model to ensure it follows the BIM protocol and that the data is secure. They are not a BIM co-ordinator and have no responsibility for clash detection or model coordination.
The Common Data Environment (CDE), is the single source of information for the project, used to collect, manage and disseminate documentation, the graphical model and non-graphical data for the whole project team. The information manager manages the common data environment.
An information container breakdown structure and a federation strategy together establish the rules for combining and segregating information containers - where an information container is: ‘…the unique identification of a file. For a construction project, an information container could be a cost plan, a programme, a drawing, a geometric model etc'. Ref Information management according to BS EN ISO 19650 Guidance Part 1: Concepts, second edition.
NB. The process of federation is criticised for not being genuine collaboration. This may be resolved by the development of Level 3 BIM, which involves the creation of a single, online, project model worked on and available to all parties. Whilst the benefits of this are clear, a step change is required in interoperability and collaboration, and the resulting copyright and liability issues may be more difficult to resolve than they seem to have been for level 2.
 Find out more
 Related articles on Designing Buildings Wiki
- Asset information.BIM.
- BIM execution plan.
- Construction Industry Council.
- CIC BIM Protocol.
- Clash avoidance.
- Construction Operations Building Information Exchange (COBie).
- Collaborative practices.
- Employer's Information Requirements.
- Government Construction Strategy.
- Information manager.
- PAS 1192-2.
- Soft landings.
- Types of building information model.
 External references
- AGC ConcensusDocs 301- BIM Addendum.