Building information modelling (BIM), as a concept, has been around for more than 50 years. Parametric software needed to facilitate the concept has been commercially available since the release of Vectorworks in 1985. For those entrenched in the AECO industry, BIM is a term that has become ubiquitous in all phases of construction. It is touted as the solution to the industry’s productivity and waste challenges. What’s more, seemingly every design consultant and general contractor in the industry has vast BIM experience with endless capabilities and markets them accordingly. Yet, with all this experience, capacity and knowledge available, where is all the BIM? Why isn’t every project reaping the rewards of this widely available practice?
To be fair, many in the industry are accomplishing some form of BIM; although, rarely in the revolutionary, fully collaborative, productivity generating way that we have all been led to believe is so easily attainable. If we are to accept what some companies advertise, it is easy to assume that by injecting some technology into the traditional process, the benefits of BIM will simply be a consequence of using that technology. Here lies the biggest challenge to seeing real progress in the industry in terms of BIM adoption. Most companies are still under the impression that BIM is a technological adjustment in an unwavering process. When in fact, the technology is only the enabler of a different, more evolved process, which is essential to realizing the full advantages of BIM. Of course this begs the question: what is that process?
So, let’s take a step back and define what “BIM” means. Part of the problem is BIM means different things to different stakeholders. For example, a design consultant team may produce a digital 3D model of the building and use that 3D model to generate their contract documents. Is that considered BIM? Some would say yes, but one could argue that because all information from submission onward revolves around said documents, they are merely using a different drafting medium to produce the same deliverable at the same point in the same process. Any downstream value of that “BIM” is negated when contractors are forced to interpret the design intent from paper documents.
What always follows is the standard onslaught of RFI’s, site instructions, change orders, etc. Even when the digital 3D models are made available to the construction team, they are always accompanied by some form of data release agreement that stipulates the model is not to be used for… anything, the paper documents govern. Again, can that be considered executing BIM? Notwithstanding any advantages individual firms may see by using a 3D model to generate working drawings, for the purposes of this article, the definition of BIM must be expanded to include applications outside of those responsible for authoring the design models. The BIM must bring value to every stakeholder in the value chain.
The real value of BIM is in its ability to enhance collaboration by enabling robust information exchange throughout the building lifecycle. To truly increase efficiency and productivity while reducing waste and rework, BIM must be planned at the onset to be continuous, uninterrupted and holistic. For that to happen, there must be big changes in delivery process. This means modifications of some stakeholder’s scope, changes to, or additional, contracts introduced and, depending what BIM application is targeted as being valuable to the project, changes to schedule.
The disconnect between designers, contractors and operators must be mended in order to reduce wasteful redundancies in process. For instance, when BIM is to be used during mechanical design, an engineer will typically model the plumbing, HVAC and associated equipment while coordinating with architectural, structural and electrical models. Needless to say to coordinate meaningfully, one has to assume that the geometry being coordinated is complete and of sufficient accuracy. However, because of the usual segregation between engineer and contractor, two critical factors are left out of design coordination: code and constructability. Systems and equipment have strict building code and maintenance accessibility requirements which fall under the trade contractor’s scope of work to accommodate. Furthermore, the tools predominantly used for design modelling represent design intent only. The geometry of what is eventually fabricated and installed varies significantly and it’s not even close to what was initially modelled. Electrical design follows suit. Consequently, even a “clash free” design model will always be missing necessary information needed for installation, information only available from the trade contractors doing the work resulting in duplicate coordination.
In terms of BIM redundancies, two distinct mechanical and electrical models are done in separate phases. (If it is even possible with the schedule constraints, considering when a trade contractor is usually procured after the tender process.) In the end, one model will contain all the relevant data and one the relevant geometry, they will not be interoperable, and the as-built information will remain paper based. Remarkably, this convoluted process increases productivity and reduces enough rework on site to be considered valuable during the construction phase.
However, as it stands, BIM is still something detached, done in silos, and injected into a process that is flawed for the desired application. There is no continuity of BIM between design, construction and operations because the current processes and procedures do not allow for it. Integrated project delivery (IPD) could be a platform for real BIM integration, but first everyone involved needs to understand it can’t be business as usual. BIM cannot be an afterthought. Assumptions and expectations must be challenged early and the project processes must be designed to match the BIM application. Additionally, trade contractors must be procured early enough to contribute their expertise before it becomes modelling rework or redesign. Above all else, BIM needs to be first defined by everybody that is to be involved in the process.
Daniel Doherty is virtual construction manager at Clark Builders. He is a certified engineering technologist, and is the current chair of the Alberta Centre of Excellence for BIM (aceBIM).