Golden Rule of BIM (AEC Insight Column)1 Oct, 2008 By: Jerry Laiserin
Building owners increasingly demand improved processes and better technology to reduce costs.
Nearly 10 years ago, Paul Bell, then-vice-president at Dell (and now president, Americas), observed that in the manufacturing business, "inventory . . . is the physical embodiment of bad information." In AEC business, the cost of bad information is embodied in routine practices such as add/deduct alternates; allowances; requests for information (RFIs), addenda, and sketches; change orders and substitutions; material stored on site; contingencies; retainage; and — all too often — litigation. Just as end users and consumers in manufacturing and distribution supply chains ultimately pay all costs of inventory-related bad information, building and project owners — as end users and consumers of design and construction services — ultimately bear all costs of bad information in construction supply chains.
In this article
Paying the Piper
Whether passed along directly as change orders, hidden in excessive bid spreads and bidding surprises, or buried in someone's overhead, reimbursables, or general conditions, all costs of project information — good and bad — are absorbed by project owners. On hypothetical (but not atypical) projects, owners could pay as much as 6% of construction cost for architectural and engineering fees or creating building information. Another 6% or so of construction cost might go to a general contractor or construction manager for general conditions, fees and/or profits, or managing building information.
Yet, as I've discussed previously, numerous studies in both the United States and the United Kingdom suggest that as much as 30% of construction cost is wasted because of bad information: inaccurate, delayed, misplaced, inconsistent, uncoordinated, and so on. Thus, project owners pay roughly 12% of construction cost to create and manage building information, and inefficiencies of as much as 30% are attributable to inadequate building information.
Little wonder, then, that owners increasingly demand improved processes and better technology, especially interoperable technologies. Emergence of building information modeling (BIM) and virtual construction (VC) — also called virtual design and construction (VDC) — promises to significantly improve accuracy, consistency, integration, coordination, and synchronization of building information at all stages of the building lifecycle. If software tools for BIM and VC are fully interoperable through standards such as industry foundation classes (IFCs), then potential cost savings through reduction of bad information can be even greater.
Government buildings and health care facilities are two building sectors in which project owners have been especially aggressive in early adoption of BIM and VC technologies. Both the U.S. General Services Administration (GSA) and its Finnish counterpart, Senate Properties, have shown global leadership in this process despite vast differences in size and scope of their respective government building construction programs and property portfolios.
Figure 1. Solibri Model Checker compares model files with building codes, design guidelines, and project programs/briefs. Many building owners demand this kind of checking to ensure that the building they get is the one they requested. (Image of the U.S. Federal Courthouse in Austin, Texas, courtesy of U.S. GSA)
Both agencies demand extensive use of IFC-based interoperable software tools by their design and construction service providers, and both rely on a model-checking tool from Solibri, a Finnish company (figure 1). Solibri's model checker works on BIM and VC models and documents in much the same way that a spell checker works on text. Models can be checked against code requirements, design guidelines, or the building program/brief. GSA has enjoyed considerable success to date with Solibri on U.S. federal courthouse projects, which have complex spatial and circulation requirements.
Complex circulation patterns are just one of the special demands posed by health care projects. Elaborate requirements for building services — various piped liquids and gases, as well as stringent standards for heating, ventilating, and air conditioning (HVAC) systems — make interdisciplinary construction coordination a number one priority for most health care projects.
Jim Bostic, assistant vice-president of construction at St. Joseph Health System, with 14 hospitals in California and a $2.5 billion construction program, explained, "MEP [mechanical, electrical, and plumbing] coordination in the field has been our biggest problem. Until 2006 we still did this over a light table — a long, tedious process with lots of personality conflicts as the foremen from multiple trades tried to figure out the issues based on overlaid 2D drawings. After learning about what BIM could do for clash detection, particularly through NavisWorks, we tried it on a project at St. Jude's Hospital. Our experience on that first attempt wasn't so good — the problem was that the subcontractors were too inexperienced in BIM.
Figure 2. Vico Software's 5D Construction Suite delivers the benefits demanded by project owners throughout all phases of information modeling, estimating and budgeting, scheduling and coordination, and overall workflow. These benefits are especially important on health care projects with complex MEP systems.
"So, we recognized we needed facilitators for the BIM process. We tried two or three, but found they couldn't deliver as promised. Finally, we met Vico . . . and they have successfully facilitated several projects for us. We now have a half-dozen targeted efforts on clash detection, plus two replacement hospital projects coming out that we will do in full 4D and 5D with Vico (figure 2)."
Subcontractors initially resist the tool, Bostic said, because "they can't see the benefits up front. Take two projects: Santa Rosa Memorial and St. Joe's Eureka. The subs initially resisted but went through the facilitation anyway. The results in the field were such that every sub realized the benefit of all that up-front work — every one of them came back and said 'I can't believe we weren't doing this sooner.'"
"Each time we do it, we learn more," added Bostic," . . . how to use the tools, how to apply the tools and facilitate the process. I'm also advocating for BIM usage in the design phase. On most of the projects we've done so far, we were still working with a 2D product that was in the pipeline. Our next two will be 3D from design to 4D/5D in construction."
Follow the Money
Bostic noted "statistically, it's difficult to document cost avoidance, but we can say with a great deal of confidence that we've saved millions of dollars worth of change orders. We have three major health care projects completed already without a single claim by any contractor or sub."
Beyond construction and downstream to facilities management (FM), Bostic said, "In our long-range plan, we absolutely want to expand BIM into FM. We will update the model throughout construction and then hand off to the hospital [for them] to model energy-management strategies. We're not there yet, but that's our future intention."
At the upstream end of the process, Bostic observed that "just like subcontractors, A/Es [architects/engineers] can be a bit resistant. If you look around the A/E industry, there are many who say they're doing BIM, but they really only have one foot in and one foot out. Maybe there's only a half-dozen firms who are really doing BIM. We try to work with A/E firms as strategic partners that will do repeat business with St. Joe, but some A/Es need inspiration. So we clearly communicate that if you want to work with St. Joseph Health System, you have to invest in this process — the software, the people, the training, and so on. We don't care what tool they use for their 3D (BIM) models, as long as it's compatible via IFC with what we use for construction, which is Vico."
About the Author: Jerry Laiserin
Autodesk Technical Evangelist Lynn Allen guides you through a different AutoCAD feature in every edition of her popular "Circles and Lines" tutorial series. For even more AutoCAD how-to, check out Lynn's quick tips in the Cadalyst Video Gallery. Subscribe to Cadalyst's free Tips & Tools Weekly e-newsletter and we'll notify you every time a new video tip is published. All exclusively from Cadalyst!