The Science of Efficiency: Prefabrication and Modularization

This is the third article of a three-part series that will examine important productivity drivers representing the construction industry’s future.

Idyllic pastures in America’s heartland underwent a metamorphosis when the automobile transformed the landscape. Technology and mass production gave birth to productivity as the minds of Henry Ford and his peers improved not only the finished product but also the process. While it’s true that automation may have replaced humans in production facilities around the world, the construction industry still relies on direct human involvement to power its engine.

But what if construction projects were able to benefit from the fabrication processes its manufacturing peers use? Naysayers will argue that too many variables exist on a construction project to safely and effectively implement fabrication practices. Meanwhile, firms throughout the world are finding success fabricating bathrooms, mechanical systems, prisons and even multi-story buildings much in the same way that 20th century American companies revolutionized the world of manufacturing. Prefabrication is hardly a new concept, but it’s one that leaders in the construction industry will look to as processes morph to improve productivity.

Many contractors examine their projects from the perspective of what they can prefabricate rather than what they cannot. While some trades lack the ability to prefabricate (i.e. earthwork), more and more contractors are choosing to use a controlled environment to mitigate site risks and lower labor expenditures. Both lean construction methods and building information modeling (BIM) bare significant weight in the world of prefabrication. BIM creates spools of documents that allow for fabrication that is more accurate, while lean construction principles correlate well to this new manufacturing setting.

Many experts agree that in the future, construction will resemble an assembly line, with construction workers piecing systems together in the same way that factory workers  connect an engine to a chassis. Smart businesses are recognizing the need to build more efficiently through the dictation of the end users and customers, and few can argue against the benefits, for example, of constructing an electrical system in a climate-controlled facility, as opposed to the extreme elements of a northern winter or southern summer. On that note, prefabrication provides mitigation against safety hazards that exist in one of the world’s most dangerous types of workplace. According a survey on productivity conducted by FMI (Figure 1), 69 percent of respondents have engaged in some sort of prefabrication on their projects.

Prefabrication also allows for improved scrutiny of production rates by limiting external factors that impact construction. With the exception of extremely customized construction and construction within the bounds of unknown site conditions, there are few examples in which even small prefabricated or modularized products would not benefit a contractor. Furthermore, the list of prefabricated and modularized systems continues to grow, including mechanical, electrical and plumbing systems; bathroom pods; hospital headwalls; pipe racks; load-bearing wall systems; internal and exterior wall systems; and sectional bridges.

In many cases, mechanical and electrical contractors work in tandem to construct modular systems because it benefits the entire project, not just one party. Within the realm of integrated project delivery systems, it is common to see this type of collaboration across firms.

As with BIM research, case studies abound about contractors building complex and sophisticated projects utilizing prefabrication, all while saving time and money. However, unlike with BIM, the initial investment in prefabrication is much lower. Careful experimentation allows new contractors exposure with less risk and less investment. As with many processes, however, the greatest hurdle that these businesses will encounter lies in the human element. Should further evidence be required, another item in FMI’s Productivity Survey (Figure 2) illustrates the savings achieved through prefabrication.

Overall, 98 percent of the survey participants achieved at least one percent in labor savings. A proponent of prefabrication and modularization would argue that as the process becomes further ingrained, firms would naturally achieve higher savings through consistency, standardization and repetition. In this controlled environment, measurement is achieved through process transparency, ultimately allowing enhancements to the production techniques.

Whether inspired by the engineering spirit of the “Extreme Home Makeover” or simply recognizing similarities to the manufacturing world, contractors who participate in prefabrication and modularization have begun to revolutionize the construction industry.