Building information modelling BIM
 What is building information modelling?
Building Information Modelling (BIM) is a very broad term that describes the process for specifying, creating, and managing digital information about a built asset such as a building, bridge, highway or tunnel.
Fundamentally, the purpose of BIM is to ensure that appropriate information is created in a suitable format at the right time so that better decisions can be made throughout the design, construction and operation of built assets. It is not about creating a 3D model for its own sake, and it is not an add-on process. BIM is fundamental to the way a project is set up and run.
 How is building information modelling defined?
Transforming Infrastructure Performance: Roadmap to 2030, Published by the Infrastructure and Projects Authority 13 September 2021, defines BIM as: ‘…a combination of process, standards and technology through which it is possible to generate, visualise, exchange, assure and subsequently use and re-use information, including data, to form a trustworthy foundation for decision-making to the benefit of all those involved in any part of an asset’s lifecycle. This includes inception, capital phase procurement and delivery, asset and facility management, maintenance, refurbishment, and ultimately an asset’s disposal or re-use.’
 What is government policy on building information modelling?
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 represented a minimum requirement for Level 2 BIM on centrally-procured public projects from April 2016 where:
- Level 0: represented unmanaged CAD (Computer Aided Design).
- Level 1: represented managed CAD in 2D or 3D.
- Level 2: represented managed 3D environment with data attached, but created in separate discipline models.
- Level 3: represented single, online, project model with construction sequencing, cost and life-cycle management information.
The UK BIM Framework sets out the overarching approach to implementing BIM in the UK. It was developed jointly by the UK BIM Alliance, BSI and the Centre for Digital Built Britain to implement international BIM standards within a UK context.
The UK BIM Framework includes:
- The published standards called upon to implement BIM in the UK.
- The UK BIM Guidance Framework.
- Useful links to other resources.
 What are the benefits of adopting building information modelling?
NBS has suggested that adopting BIM can cost a practice £10,000 per workstation (ref. NBS: National BIM report 2012). However, this depends on whether implementation is simply an exercise in buying hardware and software and then training staff to use it, or whether it is part of a wider process of business change.
The BIM Task Group was created to strengthen the public sector's BIM capability and provide the information the industry needed to meet the government's BIM requirement. It suggested that '...if successfully implemented, (BIM) will help organisations strip the waste from their processes which in many cases could be in the bandwidth of 20-30%' (ref. BIM Task Group FAQ's).
The requirement for the adoption of BIM in the public sector has led to an increase in uptake, meaning that the UK now ranks alongside Singapore, USA and Scandinavia (in particular Finland) in terms of BIM usage. Adoption of BIM in the UK is most common among architects and larger contractors, while there is less adoption by services engineers, facilities managers and smaller contractors.
However, the 2017 Construction Manager BIM survey revealed 49% of clients did not make BIM a requirement on projects, and only 20% said they asked for BIM Level 2 on all projects, and a survey of 173 manufacturers published by NBS in conjunction with the Construction Products Association (CPA) in November 2017, found that more than half felt the BIM mandate had not been successful because of a lack of rigorous enforcement. (ref. https://www.thenbs.com/knowledge/nbs-manufacturers-bim-report-2017).
The 2019, the NBS National BIM Report found that 69% of respondents were aware of and using BIM. However, the report suggested there was an emerging two-speed industry, and that there was a fall in awareness of government activity. https://www.thenbs.com/knowledge/national-bim-report-2019
BIM centres around the creation of employer's information requirements (EIR), which define the information that the employer wishes to procure in order to develop and operate a built asset. Setting this out in a contract document ensures that appropriate information is created in a suitable format at the right time.
- 4D (including time / programme information).
- 5D (including cost information).
- 6D (including facilities management information).
At level 2 (the standard set by the government as a minimum requirement for public sector projects), building information models are likely to comprise a series of federated models prepared by different design teams, and including model files, documents and structured data files containing non-geometric information about the facility, floors, spaces, systems and components. Together these create a digital replica of the built asset that starts early in the project by representing design intent, but by handover, reflects what has actually been built and installed.
The creation of a geometric model as part of this process allows buildings to be conceived collaboratively and tested virtually, before they are built and operated for real. This should reduce the problems that are encountered in construction and occupation. See clash avoidance for more information.
These models are created from a series of parametric objects. Each object is defined only once and then placed in the model in multiple locations as required. If the object is then changed, these changes will appear throughout the model. This makes models automatically consistent and reduces errors. See parametric modelling for more information.
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. Creating this single source of information facilitates collaboration between project team members and helps avoid duplication and mistakes.
 What is the most popular building information modelling software?
- Autodesk Revit – (Architecture / Structures / MEP) 50%
- Graphisoft ArchiCAD 16%
- Autodesk AutoCAD 13%
- Autodesk AutoCAD LT 7%
- Vectorworks 4%
- PAS 1192-2 Specification for information management for the capital/delivery phase of construction projects using building information modelling. (Now replaced by BS EN ISO 19650).
- PAS 1192-3 Specification for information management for the operational phase of construction projects using building information modelling.
- BS EN ISO 19650. Organisation of information about construction works - information management using building information modelling.
- CIC BIM Protocol. This establishes specific obligations, liabilities and limitations on the use of building information models and can be adopted by clients to mandate particular working practices. It can be incorporated into appointments or contracts by a model enabling amendment.
- Uniclass2015. A classification system that can be used to organise information throughout all aspects of the design and construction process.
- Industry Foundation Classes (IFC). The standard data format facilitating interoperability between different software systems.
- COBie (Construction Operations Building Information Exchange). A spreadsheet data format for the publication of a subset of building model information focused on delivering building information (rather than geometric modelling), such as equipment lists, product data sheets, warranties, spare parts lists and preventive maintenance schedules. COBie presents information in a more accessible format, so that it is easier to use and re-purpose. This is essential to support operations, maintenance and asset management once the built asset is in service.
- BIM Toolkit. Developed by NBS, and offering a Digital Plan of Work to help define roles and responsibilities for preparing information and a verification tool to identify correctly classified objects and confirm that required data is present in the model.
- Asset information requirements AIR.
- Blockchain in the built environment.
- BIM 2018-2026 market predictions.
- BIM and facilities management.
- BIM articles.
- BIM dimensions.
- BIM execution plan.
- BIM glossary of terms.
- BIM level 2.
- BIM maturity levels.
- BIM resources.
- Building drawing software.
- Construction Operations Building Information Exchange (COBie).
- Collaborative practices.
- Common data environment.
- Data drops..
- Digital engineering.
- Digital information.
- Digital model.
- Employers information requirements.
- Enterprise asset management.
- Federated building information model.
- Government Construction Strategy.
- Government Soft Landings.
- Improving health and safety using BIM.
- Industry Foundation Classes.
- Information management.
- Information manager.
- Level of detail.
- MEP BIM and the building lifecycle.
- NBS Chorus.
- NBS National BIM Report 2020.
- PAS 1192-2:2013.
- PAS 1192-3:2014.
- Soft landings.