04 January 2013

It's OK to not do BIM

In my last post I made the accusation that the term BIM had been hijacked. After reading the comments in the LinkedIn posts I created, (see BIM confusion in BIM Experts group) I have to admit that the hijackers have got away with it. Besides the usual BIM evangelists reiterating their definition of BIM, comments from real users showed acceptance that the meaning of BIM has changed. It seems consensus is now that BIM describes the whole process, not just authoring processes.

I'm OK with that. My aim is to promote practical BIM, and if it is practical to accept a new meaning of BIM I'll go with it.

But if BIM means all BIM processes, then no-one could possibly be doing all of it. Which means no-one is actually doing BIM. So what name should we use to describe the BIM process each of us is doing?

Virtual Modelling

The term Virtual Design & Construct (VDC) is mentioned in the Wikipedia entry for BIM.  I read VDC as meaning BIM for the design and construction phase of a facility, separate from life cycle, facilities management and other BIM uses.
I find this term attractive because it includes an under emphasized aspect of BIM, a description of the technology, virtual modelling.
VDC sounds more like a process, which makes it clearer. One of the problems with BIM is that it can (and is) read in two ways, a process - Building Information Modelling, and as a thing - a Building Information Model. (hence the redundant term BIM model). To add further confusion there are those that propose BIM should stand for Building Information Management, or the real die-hards, Building Information Modelling/Management (BIMM).
But is VDC precise enough? If you are an architect or engineer VDC is not that definitive because you are doing the design part, not the construction part. And are you doing a process, or are you part of a process?

This is not new, so I don't claim authorship, but I propose the terms Virtual Design Model (VDM) for architects and engineers and Virtual Construction Model (VCM) for contractors and shop detailers. All of who are using a Virtual Design Construct (VDC) process.
Bring in a Virtual Life-cycle Model (VLM) , a Virtual Facility Management Model (VFM) and other V_M participants, then you have a Building Information Modelling (BIM) process.

But where is the Building Information Model? What is a Building Information Model if BIM covers all processes? Could it really literally be one humongous computer file containing everything ever done about a facility? Although technically possible in theory (and one of the fantasies of BIM evangelists), in practical terms not a reality. Therefore BIM, as in a Building Information Model, is a theoretical construct, not an actual physical thing; the name we use when all the different Virtual models created for a facility are talked about as a singular concept.

Why is a clear definition Important?

Having a clear description is important to describe to others what you do, and just as importantly, what you do not do. One our current problems is that when you say you do BIM to someone, they assume you are doing what THEY think BIM is. And as BIM now means all of BIM, you shouldn't be surprised, you haven't been precise enough.

I suggest you tell them:

We don't do BIM, we do VDM (or any of the other V_Ms).

and if you want to sweeten the deal:

Others may use our VDM for BIM, and we'll do our best to make it as easy as possible for them within the limits of the software we use.


  1. I completely agree, and from when I first heard of VDC I realised that is what most people who think they are doing BIM are actually doing...One thing is wrong thou, we need a better abbreviation, VDC sounds terrible, therefore I doubt it will catch on!

  2. Happy New Year Antony,
    Another thought provoking post. I remember back at college in the 1980's I was taught CAD/CAM as a process being Computer Aided Design/Manufacturing. It was not until I started doing CAD in the real world that it was referred to as Computer Aided Drafting. Design was still a paper based process transferred to the computer in drawing form.
    As you point out BIM has these similar murky waters. People doing any type of 3D+ Building Modelling often consider it BIM. I think this is because there is no clear definition of how much Information the "I" in BIM represents.
    This Level of Design really needs to be addressed by Clients and/or Principal Designers at contract level so they get what they are expecting.
    I am of course one of those "BIM Evangelists" you mentioned who believes the greater the BIM process the greater streamlining of Construction however I am also a realist in understanding that the BIM process will be Trimmed and Pigeonholed to suit the individual.

  3. BIMM: Building Information Modeling and Management