With the construction industry back on track, the time is right for construction firms to evaluate the emerging trends in the way construction projects are designed and constructed. Ensuring that your business models are in line with these changes will enable your company to stay competitive as our world evolves.
The Construction Financial Management Association (CFMA) reported in a 2014 article that the integration of design with construction was one of the megatrends emerging from the recession. This integration, commonly known as the design-build project delivery method, is defined by the Construction Management Association of America as “a project delivery method that combines architectural and engineering design services with construction performance under one contract.”
Citing surveys conducted by FMI, a leading provider of management consulting, the CFMA states, “One of the perennial standout requirements mentioned by [project] owners is the increasing need for greater collaboration.” During the recession, some owners focused on the lowest price. However, the article noted that “FMI’s most recent study of owners indicated that, although they are taking advantage of a low-bid environment, owners are not abandoning their approach to best-value procurement.”
Now, with the construction industry’s health continuing to improve, contractors are increasingly gaining the advantage of being able to pick and choose among jobs. This is reducing the advantage owners were experiencing by pursuing hard bids, and the popularity of design-build has risen accordingly.
An analysis by RSMeans Market Intelligence showed that after several years of increasing use of design-build (and a corresponding decrease in the use of design-bid-build), in 2010 a temporary leveling off of design-build’s growth occurred (accompanied by design-bid-build slightly regaining its percentage of use). As the construction economy has rebounded, the trend has reversed, with the use of design-build once again on the rise.
With design-build project delivery having proven its mettle, holding its ground during tough economic times, and rapidly gaining in popularity afterward, it is reasonable to conclude that design-build will be the norm in coming years. While some in the industry may see this as just another market demand they need to respond to, the design-build delivery method can bring real benefits to the owner, the contractor, and the design team.
Collaborating on construction details
A series of parking garages currently under construction in Columbus, Ohio, illustrate some of the benefits of design-build. Most notably, design-build has the advantage of considering each contractor’s workflow early in the design process.
The first garage under construction is part of The View on Fifth apartment and retail complex near downtown Columbus. Here, the project team’s early collaboration resulted in design changes to several structural elements. This collaboration enabled the project team to coordinate the typical beam size so the contractor — Dugan & Meyers Construction of Cincinnati — could use formwork it already owned. Since formwork often totals half of a concrete construction project’s cost, coordinating these sizes reduced project costs and increased jobsite productivity. Additionally, discussions with the contractor revealed that reducing the column size at each floor going up in the structure was not cost-effective because of the need to change formwork and rebar sizes to accommodate this tapering. The extra material costs required for the larger columns would be recouped in reduced labor time on-site.
The project team also realized construction efficiencies by using the pour sequencing plan provided by the contractor to ensure that no extraneous pour strips were included in the slab design. For the View on Fifth garage, the engineers altered their initial design using this plan and were able to eliminate a second pour strip in one of the garage bays. This change worked better with the contractor’s formwork schedule, reduced the amount of rebar, and in turn, streamlined the entire project schedule.
Two garages
The opportunity for the structural engineers at SMBH to collaborate with the same contractor presented itself in the winter of 2014 in the form of two parking garages in the mixed-use development of Grandview Yard. These two garages are similar in appearance and have the same owner. The first of these garages began construction in spring 2015 and the second is scheduled to start this winter. Because of the similarities between Grandview Yard O1 and O2, lessons learned on the first garage provided insight into how to achieve cost savings for the second garage.
One lesson applicable to both structures involved the foundation detailing on a 6-inch curb adjacent to the structure’s slab-on-grade. According to bridging documents for the first garage, the building’s façade, a brick facing that wraps around the columns, was designed to bear upon this curb. Bridging documents are a set of drawings and planning documents created by an owner’s design representative at the beginning of a design-build process to assist contractors in establishing their initial pricing. During construction of the first garage’s foundation, crews dug a deep footing for the entire length of the curb to get below the frost line and prevent the brick from being cracked by ground heaving. Before starting construction of the second garage’s foundation, the concrete contractor, Dugan & Meyers, challenged the design team to create an alternate detail for the foundation. Accordingly, the foundation design was revised so that the curb used the column foundations to support the brick instead of the curb itself. Eliminating the need to dig below frost depth for a long expanse of curb reduced the project cost significantly.
The design-build process also gave the project team the opportunity to balance complex considerations during the preconstruction phase of both projects. For Grandview Yard O2, the bridging documents did not address the necessity of an expansion joint in the garage slab. SMBH and Dugan & Meyers felt that accommodation of expansion was indeed required in the garage floor slab, and proposed the insertion of an expansion joint at the center of the building. The initial cost of the joint, however, along with the expenses to maintain it over the life of the building, led the developer to ask the design team to find another way to accommodate building movement. Eventually the team arrived at a solution in which the expansion joint was located between the vertical circulation tower and the garage slab itself, but this meant reconfiguring the brick detailing at the interface of the two structures. A double-column arrangement, which had previously shown the two columns aligned on one side of the joint, was redesigned to straddle the expansion joint and provide a hidden brick expansion joint. Without this solution, there would have been an unsightly brick alignment at the building interface.
Clearly, contractors see value in having early input and leadership in a project, not only for themselves but for the project as a whole. Owners and architects largely agree. When the benefits of design-build are examined and quantified for individual projects, the ways value can be achieved become clear. Saving time, money, and effort are things everyone on the project team can get behind.
Stephen J. Metz, PE, LEED AP BD+C is the president/principal at structural engineering firm SMBH Inc. in Columbus, Ohio.
