Last edited 08 Jul 2016

Project information model PIM

NB See also our Step-by-step guide to using BIM on projects supported by more than 100 linked articles.


Building Information Modelling (BIM) is a very broad term that describes the process of creating and managing digital information about a built asset such as building, bridge, highway, tunnel and so on.

In the UK, the Government Construction Strategy published in May 2011, stated that '...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 BIM 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 engineering, contractor, sub-contractors, suppliers and so on. A federated model is an assembly of these distinct models to create a single, complete model of the building. This will be developed and used through design, construction, operation and decommissioning.

PAS 1192-2:2013 Specification for information management for the capital/delivery phase of construction projects using building information modelling specifies the requirements for achieving building information modelling (BIM) Level 2 focussing specifically on project delivery. Its application begins with a statement of need and works through the stages of the information delivery cycle.

It describes the Project Information Model (PIM) as the '…information model developed during the design and construction phase of a project.' The requirements for the Project Information Model are set out in Employer's Information Requirements (EIR) and at Level 2, it is likely to consist of a federated building information model, non graphical data and associated documentation.

The project information model is developed progressively, first as a design intent model then a virtual construction model.

In the early stages, the design intent model is likely to include massing diagrams or 2D symbols to represent generic elements of the design, with some critical elements developed in more detail. As the design progresses, the it will develop and the level of detail will increase, including, first, objects based on generic representations, and then specific objects with specifications and method statements attached along with information about space allocation for operation, access, maintenance, installation, replacement and so on.

The design intent model is then developed into a virtual construction model containing all the objects to be manufactured, installed or constructed.

Ultimately, once the construction is complete, the Project Information Model is developed into an Asset Information Model (AIM), to be used during the operational phase.

The PIM should be developed in accordance with a Master Information Delivery Plan (MIDP) and delivered to the employer through a series of information exchanges (data drops) typically comprising:

These data exchanges take place at key points in the project development that coincide with the employer's decision-making processes (gateways) as defined in the Employer's Information Requirements.

The PIM is managed within the Common Data Environment. This is the single source of information for the project, used to collect, manage and disseminate information for the whole project team. Information within the CDE can have a wide variety of status levels, however there will generally be four main areas of information:

  • Work in progress.
  • Shared (or client shared) area. This information has been checked, reviewed and approved for sharing with other organisations.
  • Published: This information has been 'signed off' by the client or their representative (often the lead designer).
  • Archive. This area is used to record progress at each project milestone as well as all transaction and change orders.

The CIC BIM protocol proposes that an information manager appointed by the client should set up and manage the common data environment. The information manager is essentially a procedural gate-keeper, policing the Common Data Environment to ensure that it follows an agreed BIM protocol and that the data is secure, and facilitating the management of the federated model. Ownership of information within the CDE remains with the originator, individual models do not interact, they have clear authorship and remain separate.

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