Building Information Modelling

Building Information Modelling (BIM), we are told, has arrived in the construction industry and been widely adopted for complex projects. It is not tomorrow's vision but today's reality, and in a few years it will be standard.

These claims are made for BIM in a paper that was presented at an international conference in London in October 2008, concerning the use of BIM in the US.1 A building information model is, in essence, an information resource in relation to a particular facility to be designed and constructed, but it is also a digital simulation of the facility that provides the ability to "rehearse" construction and updates itself automatically as more information is added. Thus the model will adjust automatically to design changes.2

In its purest form, a BIM project would use a single data model for all purposes. Each participant would access the model, adding content that could be accessed immediately by all others. Exploration, analysis and evaluation would take place within the model with information being exported as contract documents, fabrication drawings, bills of materials, estimates, costs or other information.3 The model also contains information for managing the facility as well as constructing it.

That, anyway, is the ideal. However, the author of the paper referred to emphasises that the development of BIM to its full potential has some way to go. At present, there will rarely be a single model on a complex project. More commonly, each participant will have its own model, which interrelates with the others. Further, the model (or, more accurately, the series of interrelated models), does not usually contain all the construction details required for a project. Thus the contract documents will include some 2D information to supplement the information in the model.4

Indeed BIM can simply be used by a designer as an aid to the traditional design process. This has been described as simply CAD on steroids,5 and plainly the advocates of BIM envisage that it will generally be used more ambitiously than this.

The technological challenges seem formidable. In theory, different models will communicate seamlessly. This, though, is described as an aspiration, not a reality, under current technology. Differences in capability between BIM software mean that there are real risks of data being changed or lost.6

However, there are also perceived problems or obstacles to use of BIM – at least, in the US – of a business or legal nature, due largely to liability concerns. In particular, it is said that designers are the main problem. BIM can, it is thought, increase a designer's potential liability, and because they do not share (at least, to the same extent as others) in the economic benefits of BIM, they have little incentive to adopt the BIM process. Yet it is designers who must adopt and invest in the new technology. Design professionals are...