BIM is about information, not process
We all recognise the benefits that BIM can bring to projects. But consultant and long-standing BIM advocate Ray Crotty warns against overcomplicating things in the charge to efficiency.
As Building Information Modelling gathers more momentum, a worrying trend seems to be emerging. The process issues which surround BIM have come to dominate the discussion, obscuring the central technical innovation – the perfect information that BIM systems can generate about the building.
The defining feature of BIM is the use of “intelligent”, 3D modelling systems for designing buildings. BIM enables the user to insert accurate, fully detailed building components at specific points into a computerised 3D representation of a building. The model is assembled in a manner that is highly analogous to the process of constructing the real building.
Modelling systems can generate design information that is richer, far more accurate and more fully coordinated than drawing-based systems are capable of. They can generate “effectively perfect” design information that is:
- Trustworthy – it does not need to be checked before re-use.
- Computable – it can be passed from one computer system to another without human intervention
- Intelligent – it can be used to embed aspects of human knowledge and rules about the physical world.
It can be incredibly difficult to ensure that drawing-based information is internally consistent, that it’s properly coordinated with related documents, that it’s complete and correct and that it is clear in its representation.
The poor quality of information contained in drawings undermines all areas of construction activity. It makes design processes error-prone and inefficient. It makes effective, competitive procurement of contractors impossible, because drawing-based information is inherently incapable of generating accurate, complete scope documentation. This makes it impossible to evaluate competing contractors’ bids effectively, which in turn makes it impossible to challenge and eliminate spurious or predatory tenders for construction work.
“BIM, when it becomes mature and established in the industry, will enable design, procurement and construction to be carried out on the basis of effectively perfect information. Getting to that situation, however, has become a bit of a circus.”
The result is that construction contractors compete more on their ability to win projects and manage claims, than on their ability to carry out the actual construction operations efficiently and economically. The distressingly low levels of profit in contracting and the persistent failure of the industry to improve its productivity are a direct result.
Poor information and the difficulty of accurate scope definition also lead directly to the industry’s dismal record of project cost and schedule overruns.
So three of the main areas of strategic failure in construction – profitability, productivity and predictability – can all be attributed directly to the poor quality of information inherent in the use of drawings to develop and communicate the design of buildings. BIM, when it becomes mature and established in the industry, will change that because it will enable design, procurement and construction to be carried out on the basis of effectively perfect information. Getting to that situation, however, has become a bit of a circus.
As noted above, the key feature of BIM is the use of intelligent modelling systems to generate high quality information in the design of buildings. Such systems are now available for all of the major design disciplines and for some of the specialist building analysis activities. Clearly, in the design phase of a given project, these systems will need to share and re-use each other’s data easily and accurately. And, having created such high quality information, it’s going to be important to maintain its integrity through the subsequent procurement, construction and handover phases of the project.
This introduces two challenges: how to exchange data between systems with different internal methods of representing and storing data; and commercial and contractual relations between the firms involved in these exchanges.
The government’s BIM Task Group has done good work in promoting BIM and in analysing the practical issues involved in Level 2 BIM. Inevitably an element of hype has crept in – “buzzword bumph” as Building columnist Tony Bingham recently called it. And as I said earlier, the process issues which surround BIM have come to dominate the discussion. The key concern is that the processes in question are largely about the way we do things today – drawing management and so on.
The proposed solutions – creating British Standards to embody today’s practice in these areas might be harmless in other circumstances, but when these subsequently become subject to the government’s “BIM by 2016” mandate, there is a danger that those particular solutions will become cast in contractual concrete: processes as an end in themselves, smothering initiative and stifling innovation.
There is also a significant danger, already evident, that the initiative will generate yet another layer of “validation” and “certification”, more box-ticking and check-listing.
To avoid that outcome we must refocus on the technical modelling issues and develop a more light touch, open-minded approach to the softer, process side.
Ray Crotty is managing director of C3 Systems. www.c3systems.co.uk