When a construction job untethers itself from the rule that the construction needs to occur at a fixed and unique site—the permanent home of the project—a lot of new doors open. The same goes for tossing out the idea that quality construction has to be unique, and can’t have parts that are replicated. Enter modular building.
There are many advantages to offsite building for owners and contractors who have the resources for upfront costs—namely reduced materials waste plus time and labor savings. A continued shortage of skilled workers might make more companies turn to offsite building. And crises like the current Covid-19 pandemic are creating situations when modular building is a necessity.
What is offsite building?
Offsite building, also known as prefabrication or modular building, arose from the intention of streamlining the construction process and increasing construction efficiency. These all refer to the production of part of the construction entity or product off site.
Off-site building can be the construction of small components that will be fitted into a larger structure once it is built in place on the construction site. This is known as prefabrication. This can include anything from structural insulated panels to electrical or plumbing systems. Modular construction typically refers to the offsite contruction of entire volumetric, modular units, such as rooms or entire apartments.
According to the National Institute of Building Sciences, “Off-site outputs include componentized, panelized, and modularized elements deployed in the service of structural, enclosure, service and interior partition systems.” Prefabricated elements can be built in a factory or contractor’s warehouse.
What is modular building?
Modular building is a subset of offsite building, and it means the construction of an entire and complete volumetric unit which is assembled and shipped at up to 95 percent finished before it reaches its installation site.
Modular construction has been around for a long time but hasn’t always been popular, as it was seen as creating a lower-quality construction product. However, the need for greater efficiency in construction post-downturn brought it to the surface again over the last decade.
For example, Marriott announced its modular initiative in 2015, which included the world’s tallest modular hotel in New York, slated to open this year, as well as 50 other modular structures. Sources say the international mega-chain took these steps to refill the post-recession pipeline, and because the labor shortage was dragging out their building schedules.
Again, in modular building, rooms or whole sections of a building are built on an assembly line and then shipped to the permanent building site. There, the modular components are joined to form the final structure. Sometimes, part of the structure that includes spans or large openings is still constructed on site. So essentially, different parts of construction can be occurring at the same time—some of them on site and some at the factory.
Pros and cons of modular building
Let’s review the cons first. As a contractor or owner, you have to be able to pay the overhead for use of the factory floor and the consistent payroll of employees, instead of running on a balance of equity and debt like construction usually does. There are also some costs to transporting the modular units, as they have to be wrapped and protected somehow. And critics point out that modular buildings, especially homes, might run into trouble when they aren’t built to be flush with the actual site foundation.
However, champions of modular building say the many benefits outweigh the extra costs. Those benefits include safer working conditions, because safety practices are more easily regulated on a factory floor, and all work is done at one level. Weather interruptions are removed from the equation, speeding up the building process. Supporters say the building of identical parts in a factory setting also increases efficiency, reduces materials waste and ensures consistency of quality.
Modular construction and Covid-19
One of the biggest issues facing the U.S. healthcare system in its response to the current coronavirus pandemic is the shortage of hospital rooms and beds.
While some existing buildings are being converted to house patients, hotels and other buildings aren’t ideally outfitted to be hospital rooms—and there has been some pushback from neighbors.
Modular units can be quick to build, and could be ideal in providing proper isolation for Covid-19 infected patients.
Whether there’s time to build modular hospitals for the current outbreak or not, it may be an option the country will want to employ to prepare more for future outbreaks. And with the labor shortage the industry was already facing, offsite building could become a crucial method of creating the housing and infrastructure we need at a faster rate.