Although traditional site-built construction companies are sometimes portrayed as fearing competition from modular builders, many of them have been relying on their own offsite techniques for years.
These large contractors incorporate prefabrication into their workflows whenever possible in what they say is less about turning away from traditional site building and more about having another tool in their arsenal of options to help meet clients' demands for cost-effective, on-time construction.
In projects ranging from hotels and hospitals to data centers and warehouses, they are incorporating components that have been fabricated off site such as patient headwalls, single-trade plumbing assemblies, multi-trade MEP racks, exterior wall panels, bathroom pods and pre-assembled door units. Some are even using or considering full-volumetric modular builds, where as much as 90% of the work is done offsite.
In some cases, clients have asked for offsite approaches but in others the contractor suggests them as a way to cut costs and construction time. The GCs that have embraced prefabrication say it’s a natural part of their evolution in meeting clients' needs.
"Our focus is on improving our customers' experience and this includes using prefab components when and where we feel we can," said Nate Haack, senior director of equipment and supply chain management for Mortenson, which has used prefabricated components in its projects since 2012, first in Saint Joseph Hospital in Denver, a project that encompassed 376 prefabricated headwalls, 440 prefabricated bathroom pods, 346 exterior panels and 166 multi-trade racks. Surgical rooms also employed a modular system above the ceiling that provides flexibility for any future renovations in the operating rooms.
The benefits of offsite construction stem from the assembly line efficiency and climate-controlled environment of factory production, said Michelle Meisels, Deloitte’s engineering and construction practice leader and author of Deloitte's 2020 Construction and Engineering Industry Outlook
“Modularization and prefabrication not only can save on labor costs but shorten the project schedule with less labor required onsite,” she said.
The advantages go well beyond time saved, according to Haack, including decreased waste, increased site safety, reduced congestion and being able to run parts of a project on multiple shifts a day.
Other factors that often prompt clients to consider prefabricated modules are a need for resiliency and the desire to have a replicable design that can easily be built multiple times on different sites, said Kwaku Gyabaah, vice president at Clark Construction, which began using prefabricated elements on its projects about eight years ago.
"It just naturally makes sense for many owners," he said.
Even though modular construction has penetrated only about 3% of the U.S. construction market, recent projects have drawn client attention to the efficiencies that offsite building can offer for commercial projects. These include new hotels from Marriott and Hilton and several McDonald’s restaurants in the United Kingdom.
In addition, construction giant Skanska is partnering with home furnishings company IKEA on the BoKlok modular home concept and so far has developed about 11,000 homes in Sweden, Finland and Norway.
In a recent Dodge Data & Analytics study, 80% of contractors, engineers and architects surveyed reported that they saw higher cost predictability and client satisfaction when compared to traditional construction. Use of both prefab and modular construction techniques is expected to increase, the study said, with the percentage of respondents leveraging them on 10% or more of their projects rising nearly 15% in the next three years.
Benefits aside, contractors doing prefab work agree that it’s not without challenges. There are many factors that need to be considered, and not every situation is right for prefab, according to DPR Construction Project Executive Bryan McCaffrey. For instance, a recent DPR project team decided against using a prefab exterior for a hospital project because it would have limited the amount of daylight in patient rooms.
One of the most important factors for success is a mastery of BIM software and other construction technology that helps optimize the prefab process, said Gyabaah.
"To be a serious player you need a constant R&D effort, because it really is more than just flipping a switch and being able to do a prefab project," he said. "The precision needed to ensure that once these things start being assembled or manufactured that they are going to fit into place with little to no adjustment is really enabled by technology."
"Instead of design first, and then trying to see what could be built in a modular way, this is the ideal situation where all building and design disciplines come together at the very start of the project lifecycle, because this enables us to create ultimate value instead of trying to integrate modular principles later in the project."
Manager of PCL Construction's Agile division
At DPR, which has been using offsite elements for 15 years, the move to prefab really took off about five years ago when the company began embracing more virtual design and construction technologies like Autodesk Revit and other CAD systems that allow architects and designers to communicate with CNC and other machines used in the fabrication process.
“That really helped us to look at buildings as a product and see how we can design an entire project from manufacturing to assembly,” McCaffrey said, adding that all of the company's projects look to employ fabrication in some form.
To keep up with demand, DPR operates two affiliated manufacturing plants — cold-formed metal fabricator Digital Building Components in Phoenix and SurePods, a maker of modular bathroom units, in Orlando, Florida.
Other challenges include available capacity of prefab shops, a heavy upfront investment in the fixed facilities in relation to equipment and automation and the fact that some building codes and regulations haven't yet caught up to this method of construction, according to Troy Galvin, Manager of PCL's Agile division. The contractor uses prefabricated elements on a range of its project, including health care and institutional spaces, oil gas and energy sector, commercial buildings, communications and aviation sector.
Over the next three years, Galvin said, company leaders expect to see three times the growth of offsite construction in many of its North American markets.
At PCL's offsite manufacturing facility in Ontario, Canada, workers manufacture an array of items, from battery energy storage modules, pedestrian bridges and stairs, bathroom pods, exterior wall panels, plenums, operations and maintenance field offices and helical piles for solar projects. PCL also has 140 acres of fabrication and modular assembly facilities in Alberta and California that fabricate steam generators, vessels and pipes for industrial projects.
Offsite work also demands a very high level of communication among all stakeholders, from pre-design through completion. For instance, effective collaboration with suppliers is critical for timing deliveries to arrive on the day or even the hour that they're needed, Haack said.
PCL's Galvin said his company's prefab and full-volumetric projects always start with these types of early conversations.
"Instead of design first, and then trying to see what could be built in a modular way, this is the ideal situation where all building and design disciplines come together at the very start of the project lifecycle, because this enables us to create ultimate value instead of trying to integrate modular principles later in the project," he said.
These precise schedules need to be developed and communicated to all members of the project team, said Rob Delawder, construction manager at Southland Industries, an MEP building systems provider.
He said that in recent years Southland managers have seen more requests from traditional builders looking to give prefabrication a try. He and superintendent of regional projects Samir Mustafa work to make sure the entire team is coordinated even before design starts and there is "100% buy in from all trade partners, engineering and the owner as well to this approach."
The project team for the $1.5 billion medical pavilion under construction by Southland, Balfour Beatty and others at the Hospital of the University of Pennsylvania used an integrated project delivery (IPD) approach to keep everyone on the same page. It is employing prefabrication for time-intensive construction work like mechanical, plumbing and drywall. Five-hundred-and-fifty-nine mechanical racks, 504 bathroom pods and 47 zone valve boxes for medical gas are being constructed in a 60,000-square-foot factory-like warehouse and trucked to the site two miles away.
A single bathroom pod can be completed in 80 work hours and a team of 26 workers can construct 14 pods simultaneously, according to Balfour Beatty's website. The largest racks are 18 feet long, 8 feet wide and 4 feet deep and take about one day to make, Southland Project Engineer Brian Sanvido told Construction Dive.
Having to install the mechanical and ductwork equipment on site would have been much more difficult and labor intensive, he said, and hazards were also lessened because hot work like welding was moved off site as much as possible.
The system also helps to keep the workflow efficient, Sanvido said. QR codes on the materials and racks track progress and let managers know when to increase or slow production to meet just-in-time delivery to the site.
Jan Mischke, a partner a McKinsey Global Institute, told Construction Dive that industry leaders should view offsite construction as a growth opportunity, and companies like those in this article are definitely seizing it to their advantage. A recent McKinsey study authored by Mischke predicts that construction firms that embrace modular construction will see their roles change, shifting from less on-site construction to more of a commoditized approach.
While it's unlikely any of the big site-built contractors will move to 100% modular building anytime soon, it's not out the realm of possibilities. Experts point to Chicago-based modular builder Skender, which started out 64 years ago as a traditional builder, as an example of a company that's successfully made the move to offsite building.
The use of full-stack modular construction is on the horizon for other national builders, including Clark and DPR, who are considering ways to use it in their projects.
DPR's McCaffrey said the path to full stack is something the firm has been working on for quite some time and is just waiting for the right owner and right project.
“Ultimately, we will get there," he said.
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