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AECbytes "Building the Future" Article (September 30, 2006)

Building Owners Driving BIM: The "Letterman Digital Arts Center" Story

Mieczyslaw (Mitch) Boryslawski, Associate AIA
Founder, View By View, Inc.


Our world has changed, our economy has changed, and so has the design and construction industry. It is going through an overhaul never seen before by adapting smart parametric digital technology that in the past was used only by the automotive, shipbuilding, and aircraft industries. Many of the lessons and experiences learned in these industries are being transferred to the more static design and construction industry.

Building owners are pioneering this rediscovered technology, commonly referred to as building information modeling, or BIM. After all, these owners are at the very core of the design and construction industry and have the most to gain. They have the power to eliminate the unnecessary waste, in both time and resources, and the associated cost burden facing the AEC industry. Indeed, the new client mandate is rapidly changing this industry. My company, View By View, had the opportunity to implement BIM on the Letterman Digital Arts Center commissioned by LucasFilm Ltd. in San Francisco, not only for design resolution but also within the construction process. This article captures some of my insights and experiences working on this project.

Overview of the Letterman Digital Arts Center Project

The Letterman Digital Arts Center (LDAC) is intended to be the world's premier digital arts center, with cutting-edge special effects production suites and video game development. It is located on a 23-acre site in the Presidio National Park, San Francisco, California, of which 17 acres was returned to the park. Designed like a campus to house 1,500 employees, the LDAC comprises four buildings and a theatre with a total area of 865,000 square feet and an underground garage of 717,000 square feet, providing 1,500 parking spaces with four levels underground. The structure is a post-tensioned concrete frame with steel framing on the top levels. Three buildings are enclosed with external plaster stucco walls and two buildings are clad with brick panels (see Figure 1). The buildings have a raised floor system, containing the MEP system placed on the concrete floors, then covered and sealed with metal floor panels. The raised floor system is a fairly new concept in the USA but very common in Europe. Construction on the project started in January 2003 and was completed in June 2005. More information on the Letterman Digital Arts Center, including images of the finished building, can be found here.


Figure 1
. Computer generated renderings of the LDAC. The top image shows the entire campus, while the lower images show the individual buildings.

The LDAC needed a staggering amount of technology to simulate a "virtual movie set," that would allow the employees to share files simultaneously on the different screens from different parts of the buildings. Building A, shown in the lower right image of Figure 1, has a 1200 square feet server farm and an 800 square feet media production suite. Some 600 miles of fiber-optic cable runs between 3000 AMD processors, with 10 500 gigabytes ports supported by 100 terabytes of storage. With the capacity for 14,000 processors, the center can move 1,000 terabytes of data a day across the building's 10 gigabit fiber network. Digital artists can feed high-resolution footage directly to the 300 seat theater's large 49 foot by 21 foot screen in a matter of seconds. New computer infrastructure was specifically designed for this project. The raised floors of the building that accommodate the MEP system were also designed to allow access to this complex technology for future updates.

The BIM Process in the LDAC

View By View was selected to join the LDAC project management team, representing the owner and acting as a design and construction coordinator, detecting interferences between various disciplines and assisting in the resolution of design issues. The adoption of BIM technology for this project evolved over time and intensified as the benefits of creating a detailed, dimensionally accurate 3D product model became evident. BIM was adopted in the post-design phase—after most of the design documentation on the project had been completed in 2D. Initially, a polygonal surface 3D model was created to provide photorealistic views of the project for the Presidio Trust and public viewing, as shown in Figure 1. Polygonal surface models are not intelligent models as they contain only 3D geometry and surfaces with materials applied to them. The natural progression was to take the process further and create a 3D model that could be useful for the life of the project, containing accurate information on the building product systems and also creating an "as built" 3D intelligent model. To accomplish this task, View By View recreated the 3D model by implementing BIM technology, which is shown in Figure 2.


Figure 2
. The building information model (BIM) of the Letterman Digital Arts Center.

One of the most important requirements for effective collaboration using BIM is to ensure that all team members are involved in creating the core building information model. Starting with the LDAC project management team, architects, structural and mechanical-electrical-plumbing (MEP) engineers, contractors and fabricators actively followed and provided input into the BIM process. It started with the creation of the 3D structural model, followed by the architectural components, and later, as they became available, with all of the MEP elements. The other critical issue was to make sure that the latest information flowed through the process within the core building information model. A read-only server, dedicated to the BIM process, was installed in the project site office (see Figure 3). Once all the 3D data was available, it was consolidated into a single building information model, using a unique highly compressed technology developed by NavisWorks Ltd. This technology and the ability to assemble 3D large and complex models from almost any CAD application on the market today makes NavisWorks a must in the project management tool box.


Figure 3
. The Citrix read-only server dedicated to holding the single building information model.

The building information model was updated on a weekly basis and posted to the server. The management of the digital assets was the sole responsibility of View By View. When a revised model was made available for publishing to the server, the previous model was automatically updated. Any older models that were downloaded to the local PC were no longer activated since they were timed on a weekly basis. This process worked extremely well since all the team members had access to the most current information, eliminating potential communication problems that could arise by referencing the out of date model. It also minimized the request for information (RFI) process, which requires considerable resources in typical construction. However, one challenge that we did face in maintaining the integrity of the BIM was staying ahead of the many changes or omissions that occurred during design and construction, and to ensure that we always were delivering up to date "as-built" data to the client. It was not uncommon for the designers or the contractor to make changes on the job site without reflecting those changes on their drawings.

Since the design documentation for the project had been done in 2D, there were some instances where using out-of-date drawings caused problems, such as the one illustrated in Figure 4, where a steel truss was penetrating the aluminum curtain wall. The problem was discovered during a visual conflict check of the building information model and was reported to the LDAC management team. The steel frame had already been manufactured by the steel fabricator but had not yet been delivered to the site. It was modified in the shop after the problem was detected, thereby minimizing the costs of a possible change order. Another coordination problem that was detected and resolved using the building information model is shown in Figure 5.

Figure 4. The two left images are renderings from the building information model, showing the conflict between the steel truss and the aluminum curtain wall. The photograph on the right was taken from below after the problem was corrected and the steel roof properly installed.



Figure 5
. Example of a coordination problem in the elevators machine rooms that was detected and resolved using the building information model.

During this BIM process, which paralleled the actual construction of the project, many other discrepancies and unresolved design issues were found between the structural, architectural and mechanical systems. These were pointed out to the team members during the weekly variance meetings (shown in Figure 6), enabling corrections to occur often days before the actual construction of the relevant elements. By incorporating the contractor's shop drawings as another layer in this process, additional errors were found which, if left unchecked, would have resulted in considerable costs to the contractor and delays in the construction schedule. An additional advantage was that by working on the site full time, we conducted regular site walks, recorded everything digitally, and by comparing the digital photographs with the 3D model, we were able to identify further discrepancies between what was being built and what was intended. Having already constructed the building "virtually," deviations from the design became quickly evident to us.

Figure 6. The weekly variance meetings held for the LDAC project, in which many potential design problems were detected and resolved using BIM.

Unfortunately, there were a few problems that were undiscovered during the visual scanning of the building information model and had to be later corrected on the site. This was partially due to the fact that the BIM process started after the design documents were 60% completed. Ideally, if the process had begun during the early design stage, more problems would have been avoided, including the complex MEP design issues. Of course, this process is not infallible, but the earlier the process is started and the more experience one has in this field, the better probability there is of identifying and resolving potentially expensive problems.

In order to assess the benefits of the BIM process on the project, we undertook some design coordination variance cost studies. An example is illustrated in Figure 7, which shows the cost implication of incorrectly cast concrete beams. These beams, occurring in the central stairs of one of the buildings, should have been downturned instead of upturned as there are no raised floors in this part of the building. Using BIM, the error was discovered after the formwork was completed (in the orange zone in the graph) but before the concrete was poured (in the red zone), when the correction would have been a lot more expensive.


Figure 7
. A graph showing the cost implication of incorrectly cast concrete beams. Using BIM, the problem was discovered in the orange zone, when the formwork was already in place, still averting costly corrections had it been found in the red zone, after the concrete had been poured.

On the LDAC project, we found that despite the efficiency of BIM, there still exists the possibility of human error, as illustrated in Figure 8. During one of the daily rounds of onsite photography, we recognized a critical error shown in the positioning of concrete formwork, an error that was quickly confirmed by referencing the BIM. This error occurred when the formwork layout person measured to the edge of concrete slab from a column that was off the standard grid. Pouring more concrete (shown in gray in the photo on the left) in this complex post-tension slab construction would have had a serious consequence not only for the contractor but also for the entire project, as there were three more floors to be built above this floor. Because of our familiarity with the virtual model and having experienced the building spaces before construction, we were immediately able to identify the problem and alerted the LDAC management team. The problem was solved just as the concrete was being poured, saving what would have most definitely been a major expense to rectify later.


Figure 8
. Even the use of BIM is not fool-proof. The gray transparent slab shown in the photo on the left is the graphic representation of the extra slab that would have been poured if not caught by visual inspection literally minutes before the pour was to occur.

Pushing the Use of BIM Even Further

In addition to identifying and resolving coordination problems, the building information model was also gainfully used in other ways. Laser measuring and pointing devices guided by specialized software using the building information model data were used to check for the accurate positioning of pipes in the data center. Another critical use of the building information model was to simulate an emergency situation. For example, since we had a 3D model of all the complex mechanical piping located in the parking levels, we were able to simulate the height clearance required for the Presidio fire department fleet of fire fighting trucks to access the underground parking in case of an emergency (see Figure 9). The NavisWorks clash detector module was used for this clearance check. We have also discussed the possibility of installing smart dust chips technology in critical areas of the MEP building systems, such as fire sprinklers main valves. Once the smart chip detects an emergency situation, the building information model will activate the area of concern and simulate the necessary steps to be taken with the use of 3D avatars, such as those using in the online gaming industry.


Figure 9
. Using the BIM model to check for accessibility of fire trucks in the underground parking levels.

4D or construction time-based sequencing simulation was also used on this project. 248 activities were identified, on the basis of which the LDAC cost estimators created a construction time-based schedule. Once the tasks and the area of simulation were identified, a simplified 3D model derived from the BIM model was imported into the 4D application. Links were created between the 3D objects in the model and the schedule. The end result was a time-based animation, which could automatically update with any change of time for a task. One important lesson we learned from this process was that a tremendous amount of time can be saved if the naming convention for both objects (within the 3D model) and tasks (within the scheduling software) can be agreed to in advance. This will allow for much more rapid linking between the two technologies, and much less chance of omitting the necessary elements of any construction sequence.

Moving forward, we see a number of exciting opportunities on the horizon. Of immediate interest to the LDAC team is the leveraging of the building information model by facility managers for long-term operational efficiency of the Center. For years, facility management has been based primarily on text and line data linked by specialized database software. What we are proposing is to link the 3D parametric-based objects to the same external data instead of 2D line drawings. It will allow facility managers to explore critical building systems more thoroughly and accurately within the 3D environment.

Conclusions

Despite numerous design layout changes that were required by LucasFilm Ltd. due to company restructuring, the LDAC project was completed on time and below the estimated budget. There was no finger pointing during and after completion of the project as most of the problems were solved before construction. Through careful site coordination using BIM, over two hundred design and construction conflicts were identified, most of which were corrected before construction, resulting in an estimated savings of over $10 million on this $350 million project.

While our experience with this new technology was exciting and rewarding and at times frustrating, our experience with the LDAC project confirms that technology alone is not the ultimate solution. Developing and managing the partnerships between all concerned parties involved in the design-build process, particularly with owners, designers, builders and fabricators was unquestionably a critical component to its successful implementation. The Letterman Digital Arts Center (LDAC) project demonstrates that the critical decline in productivity facing the construction industry in this country can be overcome by forward thinking owners and the project management team implementing a construction management process centered around the creation of a smart virtual building information model. The real value of using the BIM process lies in the sharing and integration of information with multiple end-users, designers, contractors, and suppliers through the life cycle of the project.

It must also be emphasized that the success of the LDAC project can be attributed in large part to significant commitment made by the owner towards implementing BIM technology. Funds were allocated to the general contractor for the purchase of software applications, training and creating the 3D MEP product data for those sub contractors that were not trained in 3D technology. Integrating a smart virtual construction model into the construction management process takes intelligence, courage, vision, enthusiasm and most of all, an intimate understanding of the design and building construction processes themselves. What the LDAC project demonstrates is that far-sighted building owners who invest in the construction of smart building information models can realize significant costs savings, not only in the design and construction process but also in the maintenance and operation of the life cycle of the building.

About the Author

Mieczyslaw (Mitch) Boryslawski is the Founder of View By View, Inc., which he propelled from its initial role as an architectural visualization service bureau in 1990 to its current status as one of the first companies to have taken BIM through the entire construction process. Mitch was born in Poland, and educated in Europe, South Africa and the USA in architecture and construction project management. He is a frequent speaker on digital architecture and BIM, has been involved in international architectural competitions for the last 30 years, and has won several awards including the 2005 "Digie" Award for the Best Use of Automation-Architectural Design. His 3D digital work on the "Greening of the White House" is permanently on display at the Old Executive Office Building, The White House, Washington D.C. Together with CREST, he also produced the "Greening of the White House" interactive CD-ROM, an environmental project funded by the department of Energy and published by the American Institute of Architects, Washington DC. The CD-ROM was demonstrated by the then First Lady Mrs. Hillary R. Clinton and premiered on the "Good Morning America" TV show. He can be reached at Mitch@viewbyview.com.


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