AEC

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

1 Dec, 2007 By: AIA ,Rick Rundell

Debunking a few more misconceptions and looking at the realities of BIM and Autodesk Revit.


If you've considered moving to building information modeling (BIM) in your practice, you may have heard some common criticisms about BIM, such as:
  1. Productivity suffers during the transition to BIM.
  2. BIM applications are difficult to learn.
  3. BIM disrupts established workflows.
  4. Owners and contractors benefit most from BIM -- not the designers.
  5. BIM increases risk.

Don't take these complaints at face value -- they shouldn't impede your transition to BIM. In last month's column, "The Five Fallacies of BIM, Part 1," I discussed the first two of these concerns. Let's continue and look at the rest to see what the facts tell us.

Workflows
The concept of workflow has two dimensions: the progress of an activity as it moves through a company and the rate at which this progress takes place. Does BIM affect workflows?

Absolutely, BIM affects workflows -- the progress as well as the rate. But the reality is that the workflows it disrupts are inefficient ones -- workflows that you are probably seeking to change if you are looking at BIM. In a Revit implementation Web survey conducted by Autodesk, 82% of the respondents noted their design process was changing as a result of using the Revit platform, and once they were past the training period more than one-half the respondents experienced productivity gains of more than 50% due to those enhanced processes. Clearly BIM does affect workflows for the better, so you should look forward to, not fear, the workflow changes caused by BIM.

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Glotman-Simpson found that the workflow between its designers and drafters has changed for the better, resulting in more informed design decision making and therefore better designs, such as this mixed-use tower slated for construction in San Diego.

Glotman-Simpson is a Vancouver-based structural engineering firm that has used Revit Structure software since 2005. For this firm, enhanced collaboration workflows are blurring the distinction between the functions of the designer and the drafter and allowing it to produce more tightly coordinated designs. For instance, the designers used to rely on the drafter to cut sections or produce details so they could look more closely at the design in a particular area. Now, the designers can manipulate the building information model directly to investigate and visualize complex conditions. In addition, the drafters can focus more on how things are built instead of having to be concerned with drafting conventions and drawing production. Everyone can focus more on the intricacies of the structure itself, resulting in a better building.

Value
Who benefits from BIM? Is it the designers -- whether they work in architectural, structural, or engineering firms -- who reap the benefit? Or is most of the value of BIM realized "downstream" by contractors and owners?

The answer is that both benefit. By reducing the duplicated efforts of conventional drafting and coordination methods, BIM allows the designer to focus more on high-value design, understand more about the design earlier through analysis and visualization, and deliver as much value to the owner as possible. The client gets better use of resources on the project and a more predictable outcome. The contractor gets higher-quality, more complete construction documents, making for a smoother, more predicable project delivery.

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RTKL uses BIM on projects (such as the hospital shown here) to improve its own quality and efficiency and to provide downstream value to its clients and its clients' contractors.

RTKL is a global architecture, engineering, and planning firm with offices around the world. The firm began using Revit Architecture software in 2003 and subsequently implemented both Revit Structure and Revit MEP software, using the Revit platform and building information model for early informed design decision making and coordination with its clients and the clients' builders. For example, RTKL used the Revit platform on a recent hospital project. Throughout design and pricing, the building information model was used in real time during owner meetings, enabling RTKL to work directly with its clients and provide them with immediate visual references of the spaces they desired. Design changes automatically rippled through to all affected drawings at one time, allowing RTKL to complete an already tight schedule and overcome a severe staff shortage during the production phase. In addition, the building information model was used to provide the contractor a superior set of construction documents with more details to describe the complex building geometry resulting in better pricing and execution during construction.

Risk
Let's face facts. Buildings are commissioned, designed, and built by humans -- so human errors are inevitable. Mistakes or misunderstandings can be expensive and aggravating. But does sharing a building information model increase the chances of mistakes and misunderstandings? Does it increase a designer's risk of errors?

Not necessarily. BIM provides a way to reduce the risk of errors that occur in the design process. By extending coordination across the entire design team, even across disciplines in some workflows, a purpose-built BIM solution such as the Revit platform can increase the likelihood that human errors are caught and corrected during the design process. With automatic document coordination and with clearer project communication based on consistent, computable information about a building project, BIM improves design decision making, predicting performance, cost-estimating, and construction planning.

In addition, nobody requires that a firm share the building information model if it isn't comfortable doing that. Sharing a building information model is not a requirement to benefit from BIM. For teams who are willing to collaborate that closely, sharing building information models can make BIM even more effective, but that choice is left entirely to the project team members.

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On projects such as this inner-city rehab, Donald Powers Architects has experienced a 50% drop in requests for information during construction.

Donald Powers Architects is a design firm based in Rhode Island, whose staff of architects and urban designers work on projects of varying size: town plans and urban designs, commercial and institutional buildings, even multifamily and single-family residences. To deliver quality design and enhance communication, the firm has standardized on Revit Architecture software. With more than 20 projects completed using the Revit platform, it has experienced significant productivity gains internally: 30% during design and documentation. In addition, it's also experienced a 50% decrease in RFIs during construction. By using a building information model, inconsistencies are either avoided altogether or identified and resolved early in the design process -- before they creep into the documentation set and end up as potentially serious RFIs during construction.

Five Facts about BIM
We are used to thinking about how CAD affects the design process for so long, that it can be difficult to wrap our heads around a paradigm shift such as BIM. I believe that many of the misconceptions about BIM are rooted in CAD experiences and also in the reluctance to move out of a comfort zone -- inefficient and error-prone as it may be. "Better the devil you know . . . " as the saying goes.

But BIM is a revolutionary new way of working and a new way of designing. It requires users to think about things differently. Start by throwing away those five fallacies of BIM and replace them with these five facts about BIM:

  1. Productivity improves with BIM, allowing firms to accomplish much more work with the same resources.
  2. BIM is easy to learn, because purpose-built BIM solutions work the way architects and engineers think.
  3. BIM improves good workflows and helps retool inefficient ones.
  4. Everyone benefits from BIM -- the owner, the contractor, and the designer.
  5. BIM provides a way to reduce the risk of design errors, enabling easy communication and coordination across the project team.

"We see Revit as a way to do what we do in a more in-depth and efficient way. Creating higher-quality architecture gives us a competitive advantage in the marketplace," states Douglas Palladino, principal at RTKL. Embrace the changes that BIM offers, and the results will be worth it.


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About the Author: Rick Rundell

Rick Rundell

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