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I submit that the traditional design-bid-build process is structured to minimize the need for collaboration. Designing a building requires numerous discipline-specific subject matter experts that contribute to a complex interwoven system. Efficiencies are gained when we untangle the collaboration to provide each discipline a silo to complete work packages followed by defined periods of looking up to see what each other is doing.
But efficiency is not the goal, maximizing owner value is.
The silo is strongest between design and construction teams. The manufacturers (contractors) of the product (building) are often not engaged until the design is complete. The traditional process views these entities’ contributions as mutually exclusive.
What specifically do engineers and contractors contribute? Engineers are technical experts. Engineers document owner project requirements (OPR), select system types, calculate capacities, create distribution schemes, space plan for mechanical floor space and vertical shafts, model energy use and interpret code compliance. Engineers are critical contributors to the successful delivery of a facility.
Contractors, on the other hand, are builders. Contractors understand phasing, temporary systems, safety, sequencing, manpower loading, real-time pricing of commodities and supply chain logistics. The term to describe contractor’s responsibilities is “means and methods.” Like engineers, contractors are critical contributors to the successful delivery of a facility.
The quality of each entity’s work is judged differently. An engineer is judged by how well the systems meet the intended performance, while contractors are judged by how well the project is delivered on time and in budget.
These different incentives reinforce different behaviors and lead to different recommended solutions when problems arise. The two can seem on opposing sides. Thus, stereotypes arise that engineers over-design and lack common sense and contractors just want to cut corners.
The silo between engineer and contractor is not just cultural, but codified in contractually defined scopes. The contractual intent is to compartmentalize responsibilities. The responsibility is assigned to the single entity viewed as best able to manage the risk. In fact, professional liability coverage may be impacted if an engineer steps outside of his or her contractually defined scope.
As convenient as it is to compartmentalize responsibilities, I have seen throughout my career how owner value is maximized when engineers and contractors work with a collaborative mindset instead of a liability mindset. Our different perspectives naturally lead us to focus on different project requirements. I believe this leads to better projects.
Here are three things I have learned as an engineer working at a contractor:
Meeting the Construction Budget is a Critical Design Requirement
Timely and reliable pricing is a critical component of decision-making during design.
Accurate pricing is a core competency of contractors and one of the prime ways a contractor can contribute to the design process. Another core competency of contractors is proposing ways to reduce cost (value engineering). Why? Because contractors are routinely asked to develop value-engineering ideas due to the frequency of bids coming in over-budget.
In the traditional design-bid-build scenario, contractors have not been part of the design process. Therefore, they are not equipped to understand the impact to the OPR. However, an indirect benefit of any proposed cost-savings idea is that the conversation starts flowing, which is almost always beneficial.
The engineer should review, understand and evaluate all proposed cost savings ideas. A less adept engineer may react as offended by the mere suggestion of some ideas. A more adept engineer will respond to the idea through life safety considerations, code requirements, engineering principle and owner project requirements.
Sometimes through a contactor’s diverse experience, a proposed cost-savings idea is clearly a better idea than what was originally considered and should simply be implemented. Often, there are ramifications that need to be discussed and considered.
Let’s frame this discussion around a simple cost-savings idea: downsizing distribution mains one pipe size. The engineer should consider the proposed idea through the various filters:
• Life Safety: Are any life safety systems impacted, such as fire pump capacity?
• Code Requirement: Are code-dictated limitations exceeded (i.e. 8 ft/sec for domestic water)?
• Engineering Principle: Are velocities created that will shorten the lifespan of the pipe due to erosion corrosion?
• Owner Project Requirements: Can the OPR still be met? If not, is the limitation future or redundant capacity? Could turbulence impact noise sensitive areas? Could extra pumping head compromise energy objectives for the project?
In my experience, when an engineer thoughtfully considers every idea and articulates the process behind rejecting an idea, a good contractor will understand, and the relationship is strengthened. When only the OPR is violated, the contractor and engineer should evaluate the cost benefit of the requirement and present the idea to the owner.
What process should be used when considering violating the OPR to get the project back in budget? Education.
The engineer and contractor together should educate the owner on the ramifications of the change and the estimated cost impact. The lean tool known as an A3 is an excellent way to document everything that needs to be considered when making a complex decision. The project is funded by the owner, and changing the OPR is the owner’s decision. We must all view ourselves as stewards of the owner’s money.
Many design decisions are based on cost rather than based on life safety, code or engineering principles. Examples include system type, quantity of offices per thermal zone, controls capabilities and plumbing fixture packages.
As an engineer, it is easy for me to advise that a facility is best served by a chilled water system, but my responsibility may be to inform the owner that their budget can’t accommodate it. A contractor by my side to provide reliable pricing is invaluable.
The Design Schedule should Align with the Construction Schedule
Somewhere, at some time, someone got the idea that in order to start construction prior to the design being complete, all you need to do is bring the contractor on board.
Having the contractor on board is required, but not sufficient to start construction.
I worked on a large stadium project in which the contractor, without design drawings, had to “design” ahead to locate piping and plumbing sleeves before the concrete pours of each level. When the contractor informed the engineer that the design was behind schedule, he responded: “No, we are not. We are meeting every design deliverable deadline that the architect has given us.”
The design schedule must be in sync with the construction schedule. There is no better way to accomplish this than through a collaborative pull plan.
Through a pull plan, both entities work toward a common goal to define milestone dates for portions of the design to enable construction to proceed free of constraints. In this way, the construction schedule prioritizes the design completion schedule.
With today’s supply chain challenges, substitution requests are becoming increasingly important. When the specified material or equipment is not available on time, the contractor may propose an alternate material or equipment that can meet the schedule.
Like the budget discussion above, these requests are the perfect intersection of the contractor’s priority of schedule and the engineer’s priority of performance. Through collaboration, the two align on their common interest of providing owner value.
Means and Methods Matter
Means and methods are long established as the domain of the contractor. But I hope you see a pattern that many facets of the AEC industry benefit from collaboration.
Common delegated design items include expansion-contraction analysis and flushing requirements.
Let’s consider expansion-contraction analysis: Determining how to accommodate this scope is typically delegated to the contractor after the engineer has completed the design. The selected method has multidisciplinary ramifications including floor plan and shaft allocation for expansion loops, life-cycle maintenance requirements for mechanical joints and the potential for extreme forces that the structure may not be able to accommodate.
The image accompanying this column depicts alternatives that were considered on a design-build project. The ultimate solution was refined through back and forth between engineer and contractor. For this project, expansion loops with grooved flexible couplings resulted in smaller footprint, lower forces and lower maintenance than other options. The means and methods dictated a substantial portion of the cost of the install as the project was primarily long, straight runs.
I worked on a 1 million square foot airport terminal renovation that was divided into three phases. The boundary between phase 1 and 2 was defined before the contractor was brought on board. Extensive and costly temporary cooling, filtration and pressurization equipment was needed to keep the terminal operational. The boundary between phase 2 and 3 was defined through a joint effort between engineer and contractor and was accomplished for a fraction of the cost and complexity.
The future of design includes incorporating more fabrication and assembly considerations through a philosophy called Design for Fabrication and Assembly (DfMA). The industry is recognizing that efficient reliable results that maximize owner value include consideration of means and methods.
In conclusion, the foundation of collaboration is a belief that every team member has something to contribute.
Collaboration is built on aligned purpose and respect. Engineer and contractor collaboration gives us the most leverage in improving project outcomes.
I encourage the industry to increase all forms of collaboration through formal project procurement methodology by emphasizing design-assist and design-build arrangements.
But I also challenge the industry belief that staying in our lane is the best way to minimize liability. If I stay in my lane, I may avoid blame when something goes wrong. But if I contribute where I have beneficial ideas, I may help something go right.
Justin Bowker, P.E. has been part of the engineering team at TDIndustries since 2001. He became the manager of this team in 2009 and vice president in 2016. Under his leadership, the team challenges itself to harness technical approaches to provide focused value to the owner on design/assist and design/build projects.
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