AEC

The Five Fallacies of BIM, Part 1 (1-2-3 Revit Tutorial)

1 Nov, 2007 By: AIA ,Rick Rundell

Debunking some common misconceptions about BIM.


"We'll lose hundreds of billable man-hours while we transition to BIM."
"Using a building information model is risky and only benefits the owners."
"BIM is too complicated for a small firm like ours to implement."
"We'll lose money on our first few BIM projects -- money we can't afford to lose."

If you have been considering moving to building information modeling (BIM) in your practice, I'm sure you've heard these and other concerns. But how big should these concerns really be?

This month's "1-2-3 Revit" is the first of a two-part series examining the most common misconceptions about BIM: what they are and why they aren't true. I'll draw on the experiences of Revit users to evaluate these "BIM fallacies."

Five Fallacies Surrounding BIM
Here are five of the biggest misconceptions I hear about BIM:

  1. Productivity suffers during the transition to BIM.
  2. BIM applications are difficult to learn.
  3. BIM will disrupt established workflows.
  4. Owners and contractors benefit most from BIM -- not the designer.
  5. BIM will increase a designer's risk.

Sentiments like these cause unneeded, unproductive anxiety for those within the building industry who are considering the move to BIM and potentially forestall or derail a successful transition. Let's drill down into each one of these misconceptions to get at the reality behind the fallacy.

Productivity
Most firms assume that if they implement a BIM solution, they'll experience productivity losses during the transition period. Indeed, a Revit implementation Web survey conducted by Autodesk cited an average productivity loss of 25-50% during the initial training period on Revit.

But, the reality is that any initial productivity losses during training are quickly wiped away by productivity gains. In that same Web survey, it took most respondents just three to four months to achieve the same level of productivity using Revit as with the previous design tool and after they were over the initial training slump, more than half the respondents experienced productivity gains of more than 50% and close to 20% experienced productivity gains of more than 100%.

For example, Lott + Barber Architects, an architectural and planning firm based in Savannah, Georgia, began to use Revit Architecture in 2004, and it now uses the program for all new projects. To quantify its productivity gains, the company compared the time spent on different stages of the design process for two projects of similar size and scope, using Revit Architecture vs. traditional CAD tools. As you can see from the table below, it experienced productivity boosts across all major segments of the design process and particularly in its construction documentation process.

A BIM solution such as Revit is based on the use of coordinated, consistent, computable information about a building project. Firms can save time by avoiding the manual creation and coordination of documents -- allowing them to generate project documentation faster and more accurately.

table

figure
BIM enables Lott + Barber to save time and increase productivity by avoiding the manual creation and coordination of documents.

Another example of a firm that has experienced significant productivity gains from using BIM is Walter P. Moore, a leading U.S. consulting engineering firm headquartered in Houston, Texas. Because its construction documents are created directly from its Revit Structure models, the company spends a lot less time producing documentation and a lot more time on modeling the structure. In addition, the parametric change engine at the heart of the Revit platform automatically coordinates changes and maintains consistency at all times. So, when the model changes, all affected views, drawings, and schedules are instantly synchronized. Revit Structure also offers an integrated design and analysis environment. As users create the physical design model, the program automatically creates an analysis model and keeps it in sync with the design model and the documentation, increasing productivity by avoiding duplication of effort and manual coordination. By focusing on the accuracy of the building information model, the designers and engineers at Walter P. Moore improve both the quality of their design as well as the quality of their drawing deliverables.

figure
Walter P. Moore uses Revit Structure to increase productivity and avoid duplication of effort and manual coordination.

Accessibility
Anxiety concerning loss of productivity is accentuated by fears about how long it will take designers -- who are so familiar and comfortable with existing CAD tools -- to transition to a BIM solution.

In reality, purpose-built BIM solutions are created specifically for the design disciplines they serve. Revit, for example, is built specifically as a tool for thinking about buildings, so it behaves the way a building designer expects. As a result, for a design professional, a software solution such as Revit can be easier to understand than more general CAD or modeling applications.

Martinez + Cutri Corporation is a San Diego-based firm that uses Revit Architecture to deliver architectural, interior, and urban design and planning services. The firm began implementing Revit Architecture in 2003 by training three people at a time, in two-week sessions. In Week One, they would learn the basics of the software, and by Week Two they were working on a real project. Their experiences mirror those of many other Revit users who have gone directly into production with the software after a very brief training period.

figure
With little more than a week's worth of training, designers at Martinez + Cutri started using Revit Architecture in production.

Another example of a Revit customer whose designers quickly transitioned to BIM is Graef, Anhalt, Schloemer & Associates (GASAI), a leading engineering consulting firm in the United States. With offices throughout the country, GASAI has used Revit Structure since it was first released in 2005. On its very first project, the project team spent about two days coming up to speed on the new software, using self-paced tutorials and viewing product Web casts -- enough to understand the basics of the product. After that short amount of training, the structural engineering technicians started in on the project, completing most of it in just three days -- an assignment that normally would have taken them three weeks.

figure
A purpose-made BIM solution such as Revit can be easier to learn than more general CAD or modeling applications, allowing firms such as Graef, Anhalt, Schloemer & Associates to start using the software in production almost immediately.

Next Month
That covers the first two fallacies. Check back next month for the last three and to hear about the experiences of Revit users who have successfully overcome these perceived obstacles.


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About the Author: Rick Rundell

Rick Rundell

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