What is BIM:
BIM is an intelligent model-based process that helps make design, engineering, project and operational information accurate, accessible and actionable for buildings and infrastructure.
BIM level 2. ... There are a number of 'levels of maturity' of BIM: Level 0 describes unmanaged CAD (Computer Aided Design).
Level 1 describes managed CAD in 2D or 3D.
Level 2 involves developing building information in a collaborative 3D environment with data attached but created in separate discipline models.
The concept of ‘BIM Levels’ (and ‘BIM Level 2 compliance’) has become the ‘accepted’ definition of what criteria are required to be deemed BIM-compliant, by seeing the adoption process as the next steps in a journey that has taken the industry from the drawing board to the computer and, ultimately, into the digital age.
The government has recognised that the process of moving the construction industry to ‘full’ collaborative working will be progressive, with distinct and recognisable milestones being defined within that process, in the form of ‘levels’. These have been defined within a range from 0 to 3, and, whilst there is some debate about the exact meaning of each level, the broad concept is as follows:
Level 0 BIM
In its simplest form, level 0 effectively means no collaboration. 2D CAD drafting only is utilised, mainly for Production Information (RIBA Plan of Work 2013 stage 4). Output and distribution is via paper or electronic prints, or a mixture of both. The majority of the industry is already well ahead of this now (source: NBS National BIM Report 2017).
Level 1 BIM
This typically comprises a mixture of 3D CAD for concept work, and 2D for drafting of statutory approval documentation and Production Information. CAD standards are managed to BS 1192:2007, and electronic sharing of data is carried out from a common data environment (CDE), often managed by the contractor.
To achieve Level 1 BIM, the Scottish Futures Trust states you should achieve the following:
- Roles and responsibilities should be agreed upon
- Naming conventions should be adopted
- Arrangements should be put in place to create and maintain the project specific codes and project spatial co-ordination
- A "Common Data Environment" (CDE) for example a project extranet or electronic document management system (EDMS) should be adopted, to allow information to be shared between all members of the project team
- A suitable information hierarchy should be agreed which supports the concepts of the CDE and the document repository.
Level 2 BIM
Level 2 BIM is distinguished by collaborative working, and requires "an information exchange process which is specific to that project and coordinated between various systems and project participants" (Source: Scottish Futures Trust).
Any CAD software that each party uses must be capable of exporting to one of the common file formats such as IFC (Industry Foundation Class) or COBie (Construction Operations Building Information Exchange). This is the method of working that has been set as a minimum target by the UK government for all work on public-sector work.
For more information on working to BIM Level 2, see the following guide developed by NBS and BSI: http://bim-level2.org/en/about/
Level 3 BIM
Level 3 has not yet been fully defined, however the vision for this is outlined in the UK Government's Level 3 Strategic Plan. Within this plan, they set out the following 'key measures' to be secured with further funding:
- The creation of a set of new, international ‘Open Data’ standards which would pave the way for easy sharing of data across the entire market
- The establishment of a new contractual framework for projects which have been procured with BIM to ensure consistency, avoid confusion and encourage, open, collaborative working.
- The creation of a cultural environment which is co-operative, seeks to learn and share
- Training the public sector client in the use of BIM techniques such as, data requirements, operational methods and contractual processes
- Driving domestic and international growth and jobs in technology and construction.