BIM & Green, Hand in hand
Better coordination brings
project in and adds value
BY BRIAN SKRIPAC
By adopting building information modeling more than three years ago, DesignGroup has capitalized on the technological shifts within the building industry. Embracing this process evolution, BIM has allowed a more effective, streamlined and cohesive workflow to develop throughout the office. While Autodesk’s Revit Architecture may have been used primarily as a documentation tool in the firm’s initial projects, it quickly became evident that the earlier it could be integrated into the process, the more productive project teams would be.
The Grange Insurance Audubon Center Project, located in downtown Columbus, provided DesignGroup the opportunity to build upon past experiences while merging technology into the earliest stages of the design, maximizing the project’s success through the creation of a Building Information Model (BIM).
The Audubon Center Project is a dynamic, sustainable urban ecology learning center that will be the catalyst in revitalizing a physically and aesthetically deficient urban brownfield site. The center’s 18,000 sf program includes a multi-purpose space, classrooms, library/bird viewing area, and administrative offices organized around a central exhibit/circulation space.
The Audubon Center will serve as a learning facility connecting the urban youth with their natural environment, and the design of building itself acts an educational element exhibiting sustainable design practices.
The building’s mass and orientation were key form-givers for the project designer, Michael Bongiorno, AIA, LEED AP. Using Revit, he was able to develop a space that would respond to the project’s programmatic needs. Understanding the building’s orientation on the site allowed him to create a linear circulation space to act as a datum into which the different programmatic elements could be plugged. With this initial paradigm and building form modeled, the client was able to visualize the project as the team moved through schematic design.
Design changes easier
Near the completion of the schematic design phase the design team learned that significant aesthetic changes were being requested by members of the owner’s fund-raising team. It was critical that the design team listen to these concerns and respond promptly. With the BIM in place the design team was able to redefine certain elements of the design and identify appropriate alternatives for owner review.
What was first viewed as a setback became an opportunity to quickly translate the owner’s new input into a strong final design without a major impact upon the overall project schedule. “Using Revit probably saved us two weeks during this redesign effort as compared to using more traditional two dimensional design tools” states project manager Keith DeVoe, AIA, LEED AP.
Continuing through the design process the three-dimensional Revit model proved to be a key communication tool, providing quick visualization opportunities not only for the design team, but more importantly for Heather Starck, director of the Grange Insurance Audubon Center, and other project stakeholders.
The BIM was regularly shared on a projection screen during design review meetings and “made it easy for us to understand the design process” explains Starck. “Live walkthroughs of the three-dimensional model allowed us to picture how spaces came together and visualize their flow from one room to another.”
Providing the client a level of insight and comprehension simply would not have been possible in a traditional two-dimensional environment. It also eliminated a redundant modeling effort that would have quickly become outdated as soon as the first change was made to the design.
Embracing the building’s form and orientation, the central exhibit/circulation space provided an organizing east-west axis, hosting many of the passive solar design initiatives the team sought to integrate. This orientation also created optimal views of the Scioto River to the south and the downtown Columbus skyline to the north.
A playful interaction between the designers and the model began, bringing clarity to the impact of sun angles on the building facade and interior spaces. This coordinated database of information generated by Revit allowed the simple change of a roof overhang in plan to be propagated throughout the project so that feedback was immediate in all views, including those where solar studies were being analyzed.
In addition to appropriately located roof overhangs, the incorporation of sun-shading devices on the south facade will minimize solar gain and provide an opportunity for the architecture to be an educational experience. The solar study function in Revit helped the design team pinpoint the precise extent of shadows at key times of the year, which became architectural elements marked by color-coded horizontal window mullions.
Segmenting the larger curtainwall of custom silkscreened frit glass serves not only as a reflection of the building design, but as a distraction for birds while reducing the visible light transmittance into the space.
Marking these key times of the year also informed the exhibit space’s interior floor pattern. Identified as an add alternate to the project, and later accepted, the design team proposed a sundial configuration marking hourly daylight entering through a rooftop oculus. Using the same solar study functionality, Revit provided the opportunity for the designers to define the key points where the sun would cast a shadow through the crosshairs of the sundial onto the floor.
Using BIM for greenness
Continuing to integrate quantifiable and sustainable initiatives into the design, the team turned to Revit to provide additional feedback typically not immediately available in the software. Wanting to leverage natural ventilation as a means to improve indoor air quality, project assistant Sarah Fortkamp, LEED AP utilized Revit’s scheduling capabilities to quantify and calculate the minimum operable opening area requirements as dictated by ASHRAE Standard 62.1. Sarah and the design team were able to take that information and integrate these openings into the defined curtainwall pattern as an appropriate design element and not as an afterthought.
Moving through a design where multiple architectural team members could simultaneously engage a single, coordinated, intelligent BIM resulted in better informed decisions made earlier in the project, therefore increasing productivity and quality. Allowing for a holistic understanding of the space, Revit assured the design team they were always working with the most up-to-date information elevating communication and coordination on a regular basis.
“Providing a seamless transition between the design and the documentation process, the software facilitated coordination of details and much of the other mundane drafting tasks, enabling us to continue focusing on the overall design” explains project architect Yanitza Brongers-Marrero, AIA, LEED AP.
Because the building’s structure is exposed, early feedback from the structural engineers at Shelley Metz Baumann Hawk (SMBH) was an important part of the design. Integrating SMBH’s structural BIM allowed for multiple structural beam and deck system options to be explored. Due to the technology’s interoperability, “the design and structural BIM models were easily exchanged throughout the project, minimizing the need for lengthy coordination meetings” says Stephen Metz, PE, LEED AP, principal at SMBH. This increased collaboration and communication between disciplines and helped to reduce many of the uncertainties that often arise as projects develop. “With all of the structural elements present in the model there was no need to waste time sketching out details and scenarios, we could just spin the model around to examine the situation which helped to move the coordination process along” explains Metz.
Eye on budget
Managing a series of possible add alternates the design team also needed to keep a close eye on how their decisions were impacting the overall project budget. Continuously able to represent materiality, shaded views were readily available as powerful tools in conveying design intent for the cost estimating team. With both the structural and architectural models in Revit, the team was able to quickly react to a suggested cost-saving measure of dropping the steel bearing height two feet in design development, which would have been an extremely disruptive and long process in a traditional workflow.
Reusable geometry and information from the evolving BIM eliminated much of the redundant work that comes with re-drawing information during the construction documentation phase. Needing only to expose the information already present expedited the development of details and sections necessary to complete the document set. This ease of their creation also helped to identify unique conditions needing further refinement, which in a traditional two dimension CAD format would have taken much longer to find and resolve.
Documentation
The Audubon Center Project incorporated BIM beyond the design and documentation phase. DesignGroup found the BIM comprehensive enough to supply project data and calculation information needed for LEED documentation. Anticipating a LEED Silver Certification, project assistant Sarah Fortkamp, LEED AP, found much of the needed LEED design submittal documentation readily available as a simple by-product of the team’s design process and continued development of the model.
Calculated areas of operable windows generated during schematic, design remained up to date and readily available for documenting compliance with Indoor Environmental Quality Prerequisite 1, Minimum Indoor Air Quality Performance, and Credit 6.2 Controllability of Systems, Thermal Comfort. This building feature was also documented as part of the anticipated minimum 42% energy cost savings, earning all ten available credits in Energy and Atmosphere Credit 1, Optimized Energy Performance.
Given that the designed vegetated roof was an add alternate, the team found it challenging to achieve the Sustainable Site 7.2: Heat Island Effect, Roof credit. While a high albedo white roof would have provided a high enough SRI value to achieve the credit, it would generate too much of a glare for migrating birds. Modeling a duller gray colored roof addressed the glare issue for birds but significantly decreased SRI value, thus not earning the credit. Revit’s capability to quantify materials gave Fortkamp the means to integrate a pattern of various albedo roofing materials, that would be non invasive for birds yet still earn the LEED credit.
With construction documents completed on time, and at a high level of coordination and quality, the bidding process resulted in bringing the project in under budget, thus enabling the owner to accept numerous alternates as part of the project, including the vegetated roof and oculus opening.
Underway
Currently as construction moves past 50% completion and on schedule, Brongers-Marrero is continuing to see the BIM as a valuable tool in managing the additional documents generated throughout construction in one central location. “Maintaining the model allows me to more quickly and accurately react to requests for information while knowing that the model will be an updated record drawing set when construction is completed at the end of June.”
Continued validation of this successful BIM project was seen recently when DesignGroup was the recipient of the Committee on The Environment‘s 2008 Sustainable Design Award for Un-Built Project from both the AIA’s Columbus and Cincinnati Chapters.
The Audubon Center Project has been and continues to be a positive experience furthering the firm’s implementation of technology. Today Revit is enabling many new opportunities within one individual software program. Tomorrow it will be the model’s interoperability that will enable the firm to broaden the use of technology to include more complex analysis and simulations to further the practice and continue to provide sustainable and efficient buildings for the client. BXM
Brian Skripac is DesignGroup’s BIM technology manager.
Architect: DesignGroup
Landscape architect: Kinzelman Kline Gossman
Civil engineer: Burgess & Niple Ltd.
Structural engineer: Shelley Metz Baumann Hawk Mechanical & electrical: Heapy Engineering
Environmental consultant: Williams Creek Consulting
GC: Gutkneckt Construction
Owner’s rep: Miles McClelland Construction and Development
