What is BIM?

July 17, 2018


The global market for building information management (BIM) is expected to be worth more than $10bn by 2022. In the UK it’s a requirement for firms working on building and infrastructure projects in the public sector, but what exactly is BIM and what are the benefits for owners, architecture, engineering and construction professionals and others?

What is BIM?

It’s a long time since designers and architects relied on pen and paper for making technical drawings that contractors could work from. Computer aided design (CAD) revolutionized the industry, allowing for detailed 2D drawings and fully 3D models that can be more easily changed, show different components of the project and present annotations and notes. 3D models can be rotated, zoomed into and even ‘flown through’ for a complete 360-degree visualisation. Models and drawings can be saved at different points, allowing for blueprint experimentation without having to start from scratch each time. Copies can easily be printed out and disseminated to all the parties that need them.

Building information modelling (BIM) builds on CAD but also goes a lot further. It incorporates 3D modelling, and this is a very important aspect, but the models are only a part of the data and information that BIM files store. BIM enables users and stakeholders to compile information on every step of a project’s entire lifecycle – from inception to completion and beyond. As well as models and drawings representing the physical schematics of the project, it can incorporate information on everything from cost to time to sustainability within a single integrated tool.

It is compiled collaboratively, meaning that all the professionals involved can bring in their own fields of expertise.


What are the benefits of BIM?

According to the NBS National BIM Report 2018 the wide-scale adoption of BIM in the UK construction industry and particularly in public sector projects is allowing the government to work towards a number of key strategic goals, including:

  • 33% reductions in initial construction and built asset whole life costs
  • 50% reductions in build time from inception to completion
  • 50% reductions in greenhouse gas emissions from the built environment and construction process
  • 50% trade gap reductions between the import and export of construction materials and services

BIM can help in all these areas as it enables a collaborative, technology-assisted approach that can lead to more efficient working in different areas.

BIM incorporates 3D CAD modelling, which makes redraws and redesigns much easier. BIM files also contain databases, allowing some items and structural parts to be quickly selected and easily inserted into the design as components, rather than having to be drawn from scratch. The collaborative aspect means that conflicts such as electrical conduits and beams occupying the same space can be resolved easily.

BIM can also go beyond the physical design of buildings and structures to incorporate elements such as project timeframes and costings that can be accessed by the relevant professionals or stakeholders.


What is the UK BIM mandate?

The UK is widely recognized as the world leader in BIM and one of the main reasons for this is the ‘BIM mandate’.

This was brought in in 2016 and essentially it requires all public sector and taxpayer-funded projects to use a minimum of BIM Level 2 (more on BIM Levels later).

The National BIM Report suggests that the government is not always enforcing its own rules but there is little doubt that the mandate has fostered a culture in which BIM usage has become the norm rather than the exception.

The study found that 78% of large companies (with 51-plus employees), 80% of medium businesses (16–50) and two thirds of small enterprises (15 or fewer staff) used BIM, suggesting it was being used on large, complex projects as well as smaller ones. Further, it found that 80% of respondents working on health or education-related projects, 83% in ‘mixed work’ and 67% of those carrying out ‘one-off new house, extension, conversion or alteration’ work have adopted BIM.


What are UK BIM Standards?

BIM can be viewed as a progressive scale of collaboration but there are certain milestones that can be defined, allowing the standards of collaboration and technology used to be divided into Levels, from 0 to 3.

Mark Bew, Chair of the HM Government BIM Task Group, said: “Standards play an important role in ensuring the wider adoption of BIM technologies, processes and collaboration by ensuring that the same accurate data can be accessed throughout the supply chain.”

BIM Level 0

At this level there is no real or formal collaboration between the design team and other professionals. It will use CAD, typically in 2D and designs will usually be distributed via traditional print-outs. As the Level designation suggests, this is not really using BIM at all.

BIM Level 1

There may be limited collaboration and a combination of 2D drafting and 3D modelling. There should be a ‘Common Data Environment’ (CDE) such as a project extranet or electronic document management system (EDMS).

BIM Level 2

This is the level required for public works in the UK by the 2016 mandate. Parties work from their own individual models that combine with external data from other parties to create a ‘federated’ BIM model.

BIM Level 3

BIM Level 3 has not been fully defined. It can be viewed as a work in progress and the UK government’s perceived ‘Gold Standard’ in BIM.

David Philp, Head of BIM at the UK Government’s BIM Task Group, wrote: “At Level 3 social performance becomes the primary objective; enabling the assets we deliver to powerfully support end-users in achieving their business outcomes, whilst underpinning the broader actions of our society and culture.

“The principal aspects of the Task Group’s business plan for BIM Level 3 include increased focus on lifecycle management and the use of real time cost and carbon data. It also seeks more service and performance based approaches, and the connection of built assets into the wider Internet of Things and smart cities.”


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