Above: Z Modular’s FLATZ 623 in Avondale, Arizona, will feature 360 units and 498 modules.
April, 2026- Stocking Island in the Caribbean Sea is known for its white sand beaches, coral gardens, undersea caves and macrofossils. It’s only accessible by boat or seaplane and has no utilities or amenities, as well as no established infrastructure. Therefore, when the team behind the Coconut Club wanted to build a full-service beach club on the island, it turned to design-build firm Roxbox for its experience in modular construction. Winner of a Modular Building Institute Award of Distinction, the Coconut Club includes seven steelframe modular buildings that were built off-site at Roxbox’s facility in Houston and transported to the Bahamas using flatbed trucks, ships, barges, floating docks and a track crane.
The Coconut Club’s remote location is obviously unique, but the same modular construction techniques are increasingly being requested for projects in urban areas, affordable housing initiatives, disaster recovery and resilience projects, commercial and institutional construction, infrastructure projects, sustainability-focused markets, and emerging markets.
The Modular Building Institute defines modularly constructed buildings as ones where “materials were delivered to an off-site location, assembled into components or threedimensional building modules, then transported to the final site for assembly.” Modular structures must meet all the same codes and requirements as buildings constructed onsite.
Like the metals industry, construction is facing a skilled labor shortage, as well as productivity challenges and an increasing need for shorter construction schedules. In addition, environmentally conscious customers are demanding greater accountability for wasted resources and large amounts of debris. The 2026 Engineering and Construction Industry Outlook published by Deloitte indicates that many large companies in the industry are investing in capabilities to compete for mega projects, including data centers and advanced energy facilities. They also are “increasingly leveraging digital tools, modular construction and strategic partnerships to manage complexity and scale.”
A project at Atlanta’s HartsfieldJackson International Airport uses self-propelled transporters to move modules into place.
TACKLING COMPLEX PROJECTS
“Modular construction is emerging as a powerful tool for modernizing aging infrastructure while maintaining operations,” says Ross Payton, aviation studio leader and principal at global architecture and design firm Corgan. The company, in partnership with Good Van Slyke Architecture, is working on an ambitious project at Hartsfield-Jackson Atlanta International Airport: Concourse D, originally built in the 1980s for regional aircraft and which has small gates and few amenities. The expansion will increase the building size by 50 percent, as well as modernize the concourse to accommodate larger airplanes and regional jets.
At the beginning of the project, “one requirement was clear,” says Payton. “Keep gates open for 320-plus daily flights. Airport leadership wanted the expansion to be as seamless as possible for passengers and operations.”
Gate closure time was reduced by combining modular and traditional construction methods, and the schedule ultimately saved more than 40 weeks of gate closures and reduced gate downtime by 20 percent, compared to a traditional construction approach, preserving hundreds of millions of dollars in airline and airport revenue.
COORDINATION
“The modular expansions allow for new gates or walkways to be opened, which, in turn, facilitates traditional construction at the gates on the opposing side over the existing concourse,” Payton says. “It’s a carefully coordinated effort to get the modules into place in one night,” Payton continues. “We have a team of 300 to 350 people from the contractor, the engineers, surveyors, airport operations, and Mammoet, the mover, working to inspect the structural system and make sure everything is lining up correctly.
“Basically, when the airport shuts down for the night, we move in,” he explains. “By the time airport operations start again in the morning, a new module is place. Once positioned, the modules were seamlessly joined to enclose the structure and integrate building systems, allowing interior work to proceed efficiently.”
Each steel module—ranging from 29 to 99 feet wide, from 96 to 192 feet long and weighing between 700 and 1,250 tons—were prefabricated in the “mod-yard,” a 6-acre lot adjacent to the airport, which allowed the team to work more efficiently by reducing the restrictions of passing through airport security, Payton notes.
Modules were moved into place when they were in a near-complete stage, “transported more than a mile from the mod-yard across the airfield to the terminal by high-tech equipment and self-propelled modular transporters.” In April 2024, the first modular pieces were put into place, and builders estimate the project will be completed in summer 2029. For large, complex airport projects, modular construction’s chief benefit is “minimizing the duration of gate closures. Existing gates remain operational longer and new gates are opened sooner,” Payton says.
Due to the rhythmic, repetitive nature of concourses, modular construction is well-suited for airport programming. Areas like restrooms, utility rooms, back-of-house spaces and concessions can be planned so they can be constructed within a single module. The building envelope, main elements of the building system, interior framing and some finishes are completed before the move to allow for accelerated connection once they reach their final location, he says.
LEVERAGING STEEL EXPERTISE
“Modular construction brings precision, scalability and speed to an industry that desperately needs it,” says Nate Arnold, president of Z Modular, a division of Zekelman Industries, an independent steel pipe and tube manufacturer. “Traditional site-built methods can’t keep up with current housing demand—we’re facing a shortfall of 3 million to 5 million units nationwide.
“When we entered the modular space through Z Modular, it wasn’t just a business decision it was a strategic response to two challenges we saw converging: a national housing crisis and an opportunity to leverage our expertise in steel manufacturing,” Arnold says. “Our background in hollow structural steel gives us a natural edge.”
Zekelman’s Z Modular line, which includes FLATZ and FUZE, allows high-quality apartment buildings to be built in half the time of traditional methods. “What really set the foundation for Z Modular was our investment in our patented Z Block,” a modular connection that ensures even stacking, Arnold says.
“The cast steel corner connection system gave us the structural precision and strength we needed to bring steel-based modular design to life at scale.
“From there,” he continues, “we knew we could standardize designs, control the construction environment in a factory setting and deliver a better product faster. That level of repeatability and engineering accuracy simply isn’t possible on a traditional job site. We’re not improvising in the field we’re assembling a product that’s been designed to fit together perfectly every time.”
Z Modular also is using automation to increase quality, incorporating robotics and advanced manufacturing techniques to reduce variability, improve safety and increase speed without sacrificing precision.
CONSISTENCY IS KEY
Z Modular has nine active properties, totaling about 2,000 units, and four additional properties in development, which will add more than 1,000 units, Arnold says. The company has reduced the typical apartment construction timeline from 14 months to around 9 months, “and we’re pushing to get it lower. That’s a game-changer when you’re trying to meet demand at scale,” he points out.
“Beyond speed, there’s cost control. Our standardized modules and factory-based processes cut down significantly on waste, improve resource use, and make budgeting more predictable for developers and owners.”
As Z Modular has increased its footprint, one of the most important lessons learned has been the value of control. “When you’re dealing with modular, especially steel-based modular, every detail matters, down to the millimeter,” says Arnold. “That’s why we brought as much of the process in-house as possible, from steel fabrication to structural design and even property development. When you control the inputs, you can control the outcome. We’ve also found that close monitoring of tolerances and material handling is non-negotiable. A slight deviation in a weld or a misaligned framing piece doesn’t just cause a minor issue. It affects the entire stack.
“Modular isn’t just about building differently it’s about operating differently,” he continues. “You need to think like a manufacturer, not a traditional contractor. You need reliable inputs, efficient processes and a deep understanding of what your target market actually needs.”
The modules for FLATZ and FUZE are up to 90 percent completed off site before being transported to the property location for final assembly.
REALIZING POTENTIAL
According to PwC, prefab and modularization’s potential will increase when it’s paired with AI, robotics and automation. “These technologies are transforming how capital projects are planned, executed and optimized. Modular and digital delivery models inherently support this shift. Factory-controlled environments reduce waste, cut carbon emissions by about 34 percent and improve safety through standardized, repeatable processes. Off-site fabrication also limits site disruption and accelerates commissioning, helping firms meet growing community and regulatory expectations.”
“Modular isn’t just traditional construction in a different location; it’s a completely different delivery model,” Arnold says. “To do it right, you need experienced professionals who understand every phase: from design and engineering to manufacturing, logistics and final assembly. And they need to work as a cohesive unit. If one part of the process is out of sync, it slows everything down.”
The technology still faces external headwinds. Lending institutions sometimes hesitate to fund modular construction, and state and local governments often haven’t modernized their zoning or building codes to support off-site construction. “Until that changes, we’re still working uphill in a lot of markets.”
Ultimately, “the potential of modular is massive, but it’s not as simple as swapping one method for another,” Arnold says. “It takes experience, investment, coordination and, above all, commitment.”
