Friday, June 29, 2012

“Explain yourself!”

Orders my overly critical friend.
Since my post a couple of days ago, he’s been labeling himself as the Devil’s Advocate’s Devil’s Advocate or DADA for short;
He is not liking my flippant dismissal of the article that (to quote it again):
has put to rest the question of whether BIM pays off for small-scale facility upgrades”.

So, I suspend for the moment my self-imposed limit of 225 words-per-blog-post and embark on a detailed explanation, why I wrote what I had, deeply offending my BIM enthusiast friend and many others I presume, along the way.

“Apples for apples”
While there is limited amount of project data provided within the article, it is hard to see, how these would (both the noted and omitted ones) possibly assemble in an environment where the first project becomes a ‘control group’ for the second.
A ‘control group’ is generally used as the benchmark against which to detect and measure changes that may occur in the experimented on groupdue to the effect of changing a single variable (use of BIM in this case).
I just don’t see close enough resemblance between the two, without a lot of mathematical gymnastics applied to the conditions.

“The first step of the plan was to demonstrate the value of BIM with an apples-to-apples project analysis, comparing a just-finished renovation using CAD with a second one using BIM.”

Note the ‘just-finished’ label describing case 1 (traditional) – when in fact the text below says it was completed between November 2008 and May 2009. The BIM one on the other hand was delivered between January and July 2011. Even if we ignore the inaccurate use of “just-finished” of the first statement, the time lap between the two cannot be. Two years are a long time in construction where many factors can dramatically change, especially when these two years straddle one of the wobbliest stages in recent AEC history.

“Both projects are adjacent to the same occupied space. It was key for us to be able to get that comparison with the complexities of the space being the same for both projects,” says Michael DiFranco, manager of facility planning and development for Bronson.

I’m not a healthcare design specialist so I can’t confirm or otherwise with authority if the two spaces indeed could be considered to be the ‘same’, however when I look at the supplied floor-plans I’m left with a nagging feeling that this statement is stretching the facts a bit too far.
The first one has significantly larger and fewer rooms than the second, they are of different sizes and adjacent to different spaces. They serve different functions and can possibly be involving very different sets of equipment suppliers and installers.

Then come the ‘hard facts’, figures tabled and trends highlighted. Manipulative use of colours (red/green) arrows highlighting rises and drops.
Despite this scientific looking document, we do not get to know how for example, budgets were arrived at in either of the cases, a change in the QS personnel  (quite possible in the 2 year time frame covered) on its own can make the two projects comparisons impossible and the data unreliable.
The drop of change orders could be contributed to myriad reasons too, more /less competent people on either side could impact on the numbers, so could client initiated changes, amended scope, delays in some supplies, supplementation of long-lead items etc.
Being a GMP contract, the general contractors (if there were 2 different ones) could have chosen to absorb certain cost with the view of keeping a potentially lucrative client. Even the same contractor could have treated the two projects significantly differently due to change in market conditions, labor costs etc.

“The biggest benefit of using BIM is coordinating construction virtually instead of in the field. This has long been the advantage of BIM on large projects,” says Karl Kowalske, principal at Diekema Hamann, the architect and engineer of record for the Bronson projects.

While this may be true for the quoted company, if it is, it is not something I’d be proud of.
What they are confirming here is that sufficient pre-construction coordination has been universally lacking on non BIM projects, delivered via CAD on their previously delivered projects.
The stated $ 40,000 fee for ‘BIM’ is also something one should be curious about, what were the ‘additional’ services that BIM was bringing for the client for ‘extra money spent’? In theory, there could have been  ‘traditional’ consultants out there in the market place able and prepared to provide exceptional results for the same scope without asking to be paid for the BIM part too.
Had the client representatives had the chance to opt in/out of BIM with full knowledge of what they were getting?

“BIM creates many benefits, but using this tool is not free, especially when the owner specifies a data-rich model designed for ongoing facility management use. Kowalske says paying the architect/engineer to develop the BIM documents typically results in savings for the owner.”

The above statement is probably the most damaging for BIM, while still true in parts.
First, BIM is not a tool, though it uses BIM-enabled tools. Data rich FM ready models can be produced from well-maintained design/construction models at a reasonable or no extra cost, especially if this process is compared to preparing traditional as-builts, usually included in the base contract cost.
BIM, especially labeled as a ‘tool’ does not on its own save money for clients, competent people using good tools and processes do.
Also manipulator PMs, questionable contracts, out of synch market conditions and a little bit of luck can contribute to tip the scales and deliver a windfall in savings for the client.
These are rarely listed publically.

My friend (DADA) is unhappy with me regularly barking up the wrong (BIM-promoters’) tree and tells me off when I discredit their findings.
I’m sorry to disappoint him, but someone is ought to do this.

Had the pilot-BIM-ers quoted here, predicted performance for the examined project based on numerous typical projects done through ‘traditional processes’ before and compared that to the actually achieved results from employing BIM would have had more use, I think.
Even more credibility would have been earned had they genuinely assessed the difficulties in staying on top of things using the traditional processes.
As much as we all yearn to quantify the benefits of BIM, bad examples do more harm than good.

If this was just a self-promoting blog-post (the types I’d write) – it would be forgivable, the danger is, that soon enough, software promoters, students writing essays and careless  journalist will pick up the same and use it as a ‘set-in-the stone proof’.
Pseudo-science is already widely spread within BIM, let’s not add more to it.
A bit more scientific rigor would be good.

* See the original article here


  1. I have been trying for some time to get a BIMmer to explain to me how to bottom-up estimate/budget the time it takes to produce a set of construction documents using a BIM model. No one seems capable (in the olde tymes we estimated hours per drawing sheet - quite simple and elegant really...) Your thoughts?

    BTW your blog posts are right on target! Please feel free to email me at

    John Wilhelm

  2. Yes, BIM is relentlessly oversold as the best thing for construction since the porta-potty. However, great coordination and dramatic reductions in change orders can easily be realized by good use of Navisworks, which can import many different 3-D models from many different 'non-BIM' programs. If the facilities folk have no real intention of using a building information model, then most any 3-D program can be used (with Navisworks) to save construction costs via close coordination.


    autocad solutions

  4. Good content thanks for sharing with me BIM Implementation