TPM

Structural Engineering & Design Magazine

By Sarah Hodges
Industry Marketing Manager for Building Engineering, Autodesk, Inc.

Now that you’ve figured out building information modeling (BIM), here’s another three-letter acronym for you to master: IPD. Integrated project delivery (IPD) is a project delivery approach that uses business structures, practices, and processes to encourage the early contribution of knowledge and experience by key project stakeholders. With IPD, owners, architects, engineers, construction managers, contractors, sub-contractors, and fabricators collaborate at the earliest stages of a project to assess project options against business goals and make decisions based on a best-for-project yardstick. The goal of IPD is to reduce waste and maximize efficiency throughout all phases of the project — ultimately increasing value to the owner.

Engaging in IPD can result in a more effective design and construction process. But it requires closer relationships and more collaborative business models than some firms may be accustomed to. To give you a deeper understanding of IPD and its potential benefits, let’s look at two very different structural engineering firms that are both involved in IPD projects for retailer Crate&Barrel: Thornton Tomasetti, a 600-person organization of engineers and architects collaborating from offices around the world; and Moore Lindner Engineering, a seven-person firm based in North Carolina.

The modeled section of existing pipe aided visualization of potential conflicts with the deep foundations. Proposed grades for paving and landscaping (not shown) were also modeled to ensure adequate cover over pier caps and grade beams.

Inside-out building design
With more than 160 stores, Crate&Barrel is a retail chain that specializes in housewares and furniture. All Crate&Barrel stores share a distinctive neo-modernist architectural style, but no two stores are alike. The retailer’s in-house architecture group designs each store from the inside out, based on the store’s location and Crate&Barrel’s signature display of its merchandise.

New Crate&Barrel stores have aggressive project schedules and fixed deadlines dictated by a store’s opening date, which in the retail world is sacrosanct. To facilitate collaboration and information exchange, the company requires the use of BIM on its projects. Most Crate&Barrel construction projects are good faith, negotiated award contracts with no liquated damages or incentives. So the retailer’s corporate building program relies on long-term relationships with established levels of openness and trust. For example, Crate&Barrel typically involves its steel subcontractor early in a building project, which works with the structural engineer to meet the owner’s goals relating to schedule, budget, and other issues that arise. SteelFab, based in North Carolina, is one of the retailer’s long-time steel contractors.

Owner-led IPD
SteelFab was Crate&Barrel’s steel contractor for one of its newest stores — a 28,000-square-foot standalone store in Schaumburg, Ill. For the store’s structural design, the fabricator recommended Thornton Tomasetti, a proven collaborative partner of SteelFab. “This was our first IPD project with Crate&Barrel and they did a great job of helping the team set goals and establish the ground rules,” remarked David Weihing, a vice president at Thornton Tomasetti. “Collectively we identified roles of the team members, the process of collaboration, what information would be shared, and how the team would agree on design and construction deadlines.” From those discussions the group crafted a statement of common purpose that served as an amendment to Thornton Tomasetti’s standard contract with Crate&Barrel.

Moore Lindner had a similar introduction on its first Crate&Barrel IPD project, which was a 35,000-square-foot store located in Hallandale Beach, Fla., just north of Miami. SteelFab had worked closely with Moore Lindner on previous design-build projects and, based on those successful partnerships, recommended the firm to Crate&Barrel. “A structure like a Crate&Barrel store, combined with the stringent code requirements in South Florida, meant that a working relationship with the fabricator was all the more important,” explained Matt Lindner, a principal of Moore Lindner Engineering. “Having worked with SteelFab over the years, we are as familiar with their fabrication and erection preferences as they are with our design preferences. As a result, the focus is on getting the best value for the client.” Like the Schaumburg project, Crate&Barrel gave SteelFab and Moore Lindner the freedom to work out the details of their project collaboration and formulate their own processes.

BIM-based design
Both projects had an accelerated design and construction schedule: approximately eight weeks for structural design and documentation and 32 to 40 weeks for construction. As soon as the project teams were formed, the structural engineers had to hit the ground running.

Thornton Tomasetti’s engineers leveraged the architect’s BIM-based design model to start the design process and used their own BIM software to develop and analyze the structure. Right out of the gate, Thornton Tomasetti and SteelFab worked together on strategies to frame the structure efficiently and optimize the design based on SteelFab’s fabrication and erection preferences and experience.

“The project delivery date was essential for Crate&Barrel,” remarked Weihing. “By itself, the structure of a retail store isn’t particularly newsworthy. The challenge here was to meet an incredibly aggressive schedule of seven weeks from project inception to delivery. The only way to do that was to get the whole design team working together in sync so that we weren’t duplicating efforts and wasting time due to miscommunication.”

And the key to their collaborative design effort was the use of BIM-based design models for digital design reviews and information exchange. Once the structural design was essentially complete, Thornton Tomasetti used its design model to generate a steel fabrication model for SteelFab and jumpstart the mill order. SteelFab added connection detailing information to this model and returned it to Thornton Tomasetti digitally as the formal steel submittal.

Project coordination
The Hallandale Beach project featured a similar BIM-based design and collaboration scenario. “On a typical Crate&Barrel store, the design of the super structure is relatively straightforward,” said Lindner. “Most of the work is from the column line out. There is a complexity in the Crate&Barrel architecture that translates into intense structural coordination, particularly at slab edges and in the ceiling space.” The firm started by bringing the architectural model into its BIM structural design software. Later on it added the MEP model for cross-discipline design coordination.

For clash detection, Lindner modeled the beam bridging (initially shown only as line drawings) in a congested ceiling space because he was concerned it would interfere with ductwork running through the area. “We also modeled a section of existing underground pipe by using the landlord’s as-built civil drawing to get a better understanding of how the pipe interfaced with the helical pier foundations at that location.”

This Crate&Barrel project included a highly articulated portion of structure, with multiple level of framing at intersecting angles — note beam bridging at inboard bays (center of picture).

In many traditional projects, much of this cross-discipline, model-based design information would be unavailable and this level of project coordination might be viewed as someone else’s job. The use of BIM-based design solutions enables the project team to aggregate separate design models to create a multi-discipline project model, used for overall project coordination.

Open communication
How did the geographically dispersed teams physically communicate and collaborate on these projects? “It was everything from formal review meetings at a Crate&Barrel office or web-based meetings using BIM digital models, to just quick phone calls or e-mails,” said Weihing. “The IPD process allowed freer channels of communication,” remarked Lindner. “During the design of this project, I communicated as much — if not more — with the general contractor as I did with the architect. The contractor’s experience in South Florida was invaluable in determining the most efficient wall and roof systems, for example.” This type of easy and open communication was vital for the success of these IPD projects.

Crate&Barrel has even organized what it humorously refers to as a “speed dating” project review. “On our current Crate&Barrel project, we had a meeting where reps from the owner, designers, and contractors came together for a day during design — ready with our list of issues in hand and the drawings or models we needed to communicate those issues,” said Lindner. The various teams moved from group to group and table to table, meeting with the other decision makers to resolve design issues quickly and make immediate project decisions.

Risks and rewards
Like any building activity, IPD has both risks and rewards. Liability can be a concern for some firms. When digital information created through a team effort is the basis for construction and fabrication, which party is responsible for a design flaw? IPD contracts that include shared risk and reward can mitigate those concerns, but they only go so far.

“Surround yourself with people you genuinely trust and respect,” recommended Weihing. “You have to be able to rely on the partners at the table.”

Lindner echoed this sentiment. “IPD requires people who have the same work ethic and collaborative mindset where all the players are working together to understand what’s valuable to the client and deliver that value.”

“Our experience with IPD has been very positive,” said Weihing. “No one likes contentious relationships. IPD is the vehicle that drives the stakeholders to communicate earlier in the process, minimize low-value activities, and ultimately deliver a better product.”

The benefits of IPD on these projects were striking. Unlike traditional design-bid-build or design-build projects, the structural engineering firms worked in lockstep with the steel fabricator to jointly produce the leanest, most efficient design they could. Both firms used their own design models to generate a preliminary fabrication model for SteelFab. This helped the fabricator get quantities for the steel orders and start steel detailing earlier in the process. As a result, building schedules were compressed and the teams met all their project deadlines.

Conclusion

The rise of these shared risk-and-reward projects isn’t surprising. Building industry professionals are increasingly bringing an IPD attitude to their projects, regardless of the business contracts or structures.

Sarah Hodges is the industry marketing manager for Building Engineering for Autodesk. She can be contacted at This e-mail address is being protected from spambots, you need JavaScript enabled to view it .