Adobe stock photo
When prefabricated in modules, bridge decks can be installed quickly in the field without the aid of any heavy equipment.
The prefabrication concept is nothing new in the bridge sector. Temporary bridges have long provided a smart solution when routes are lost. But the prefab process is being incorporated into transportation construction in new areas. Water and rail are two infrastructure sectors being served successfully with prefab components. A growing number of contractors are looking to the prefab process to get jobs done more quickly and safely.
In fact, contractors are devoting larger chunks of the budget to prefab operations.
FMI found that contractors on average are spending 18 percent of their time in craft labor hours on prefab for construction projects.
The engineering consulting firm surveyed 250 contractors as an update to its 2023 Labor Productivity Study of just how prefab ties to labor numbers.
Contractors said they anticipate craft hours dedicated to prefab would double to approximately 34 percent over the next five years.
FMI's 2024 update supports the idea that the industry looks to prefab as a possible solution for the ongoing labor shortages across all construction sectors.
They're familiar with the technology, too. Some 86 percent of respondents already have single-trade prefab services in place. And three quarters of responding concrete contractors said they are prefabricating on the job site, as are 57 percent of self-performing GCs.
But in the FMI survey, respondents said the biggest perceived benefit to prefab is improved quality.
One contractor believed prefab reduces the risk and variability, noted bdcnetwork.com in an article on prefab construction trends.
Reduced construction schedules and improved worker safety were cited by respondents, most of whom were MEP contractors. Others, in framing and drywall.
New Applications in Motion
The prefab concept is growing in popularity for projects that wouldn't ordinarily fit the typical construction application.
An argument is being made for the benefits of prefab in high-speed rail (HSR). A hub for construction of HSR infrastructure is emerging in California.
A joint venture pre-cast facility, the hub serves as a manufacturing facility producing wide-flange girders, deck panels, tub deck panels and piles.
The Hanford Sentinel reports more than 100 craft workers, including operators, masons, carpenters and ironworkers, are employed there.
The prefab components made there include welded wire mesh, bent and straight rebar, concrete and pre-stressed strands.
Adobe stock photo
Craig Watts, pre-cast manager, said the facility produces structural components for a regional rail guideway.
Among equipment on the site, 110-ton mobile gantry cranes are used to lift and load girders onto trailers.
"We use it to go in and out of the rows," Watts said. "They'll go over the top of a row of girders and pick it up, pull it out and load it onto a trailer."
When the pre-cast facility shuts down operations, the site will convert to the Kings/Tulare High-Speed Rail station.
HRS officials anticipate the first rail section to operate between 2030 and 2033. Trainset testing is estimated to start as early as 2028.
Could incorporating prefab and modularization into the build strategy of water projects help mitigate risks in construction sequencing?
The technology has the potential to benefit the water infrastructure industry in a big way, said one piping system consultant.
Ernie Maschner, vice president of global water of Vitaulic piping systems, believes prefab can mitigate civil-structural-mechanical sequencing.
In a Water Collaborative Delivery Association blog, he highlighted potential efficiencies in construction and scheduling and reduced dependence on labor.
"Prefabrication is not widely used on municipal water and wastewater treatment projects compared to private sector projects," said Maschner. "But its benefits are well suited and complementary to collaborative delivery projects."
Maschner believes collaborative delivery methods are optimal for prefab when the construction team and supply chain are involved early on.
"These benefits aren't available under design-bid-build delivery because construction begins immediately after bid," he said.
That rapid jump to construction "doesn't allow time for the proper planning associated with prefabrication," according to Maschner.
He believes prefab can reduce construction time by standardizing components and processes. He said modular components manufactured off site in control environments allow for mechanical systems construction that parallel site construction activities.
"This approach reduces onsite labor requirements and the potential for delays due to adverse weather conditions, resulting in faster project delivery."
It also helps when full modularization is already utilized and accepted in engineered equipment and treatment systems.
Completed modules are then released for fabrication early in the design process and delivered on site.
"Expanding the practice to pumping systems, for example, reaps the same benefit of saving time during the build," said Maschner.
Prefab also facilitates construction and storage of piping systems while site construction is under way.
Adobe stock photo
This, in turn, allows for faster install once work areas are released to piping installers.
Maschner believes modularity and prefab offer "substantial" cost savings in collaborative delivery projects.
He maintains that offsite prefab allows for bulk material purchasing, reduces waste generation and improves quality control for big cost reductions.
"Furthermore, prefabrication minimizes onsite labor requirements, reducing the need for specialized and skilled workers," said Maschner.
Utilizing a centralized prefabrication facility allows for multiple projects to be constructed at once.
The result is leveraged productivity of the facility without dependence on weather or other site disruptions.
"With the current strain on craft workforce availability, individuals that may not be available for project travel can still be utilized," said Maschner. "Streamlining construction activities and eliminating rework contributes to further cost savings."
When the fabricator can optimize design performance requirements into the build, the quality of prefab systems increases.
Maschner said coordinating prefab with the construction teams accounts for installation requirements into the prefabricated elements.
"This, combined with working in environmentally controlled conditions in an enclosed shop environment, improves the quality of the final product," he said. "Shop modularization allows for testing and certification of complete systems, reducing subcomponent testing requirements on site."
With prefab systems, the safety risks associated with site assembly are reduced, and possibly eliminated entirely.
Maschner believes it applies not only to work at heights, but welding, confined-space entry, material handling and slips and falls.
Full modularization can remove up to 70 percent of the associated hours from a job site, he said.
Finally, prefab promotes sustainability by minimizing construction waste and reducing environmental impact tied to onsite activities, said Maschner.
Factory-controlled production allow for better waste management and recycling practices.
Many project proposals now require proponents to provide adequate measures to mitigate disruption to surrounding communities.
"Reducing site labor, traffic to and from the site and diverting deliveries to a fabrication facility are strong actions toward this goal," said Maschner.
Nuts, Bolts of Prefab
FMI advises contractors looking to devote more resources to prefab operations to "determine how to do it at scale, profitably."
At the same time, companies must implement the process in a way that increases earnings across the board.
Adobe stock photo
Successful prefab practices require long-term strategic thinking and planning across an organization, said FMI. This strategy works alongside the development of a comprehensive operational blueprint.
To choose the right prefab model, the consulting firm suggests contractors create a clear vision of what they want their prefab capabilities to become.
Shift operating models, processes and systems, advised FMI. And then decide which models work best for your company.
Models, or combinations of models, can include kitting services, multi-trade services, procurement and modular services.
FMI lists serious questions every contractor should ask themselves during the process of creating a clear vision for their prefab operations.
- Why do we want to do more prefabrication?
- What is the total addressable portion of our work mix (today) that could be prefabricated?
- What investments would need to be made to scale our prefabrication capabilities to capture that opportunity?
- When fully optimized, what does the earnings stream from prefabrication look like?
- What does the return on investment look like for the enterprise?
- Do we have alternative investment options for other initiatives in the business?
- How do those options stack up against our prefabrication ambitions?
- Will prefab make the company better, more profitable and resilient?
FMI suggests contractors look at prefab as a different kind of business and seek owners and designers receptive to the technology.
"Prefabrication is a manufacturing endeavor that's different from building construction," said the consulting firm.
Contractors need to think about whether prefab will be a unique business or separate entity and how autonomously construction and prefabrication operate.
"Will prefab services be proprietary or available to other contractors? Will prefab be a profit or cost center?" the firm posed. "How will manufacturing cost overruns, if there are any, be accounted for?" These are all important questions, added FMI.
Next, contractors need to establish clear project management lines that encompass how prefabricated products are tracked, stored and billed for.
"For the industry to realize substantial gains in prefab and productivity, owners and designers need to be a bigger part of the demand equation," said FMI.
FMI's study shows the industry still struggles with broad adoption of prefab and modular construction.
Project design and coordination, stakeholder awareness and education, the mindset and culture of active players and investment in resources are challenges.
But FMI strongly believes prefab will need to become part of the construction efficiency solution. CEG
Lucy Perry
Lucy Perry has 30 years of experience covering the U.S. construction industry. She has served as Editor of paving and lifting magazines, and has created content for many national and international construction trade publications. A native of Baton Rouge, Louisiana, she has a Journalism degree from Louisiana State University, and is an avid fan of all LSU sports. She resides in Kansas City, Missouri, with her husband, who has turned her into a major fan of the NFL Kansas City Chiefs. When she's not chasing after Lucy, their dachshund, Lucy likes to create mixed-media art.
Read more from Lucy Perry here.
Today's top stories
