Getting Started with Prefabrication and Offsite Construction
Since the days of playing with Tinker Toys and Race Cars during our youth, the appeal of prefabrication has been around for many years. The number of parts, color-coded to different lengths, multi-sockets tagged to help children assemble their masterpieces with minimal effort. It is unbelievable that prefabrication is rapidly working its way into construction after those impressionable years of success with toys. Stick building projects have led to unpredictable and stale workflows causing stagnation for decades. Still, prefabrication changes the game by using reliable, streamlined processes to create accessible parts making the building process faster on the jobsite.
Prefabrication is closely associated with offsite and modular construction for many good reasons. This article will dig into the history, its definition, benefits, current trends, and the difference between offsite and modular construction.
Prefabrication by Definition
Construction jobsites are chaotic, congested, and often located in areas where movement is cramped and difficult. Getting materials and machinery can be problematic, raising costs and lengthening construction projects’ timelines, no matter their scope. Prefabrication has a substantial track record for reducing building costs, reducing labor risk, and easing the construction process overall.
Many expert sources report that prefabrication is the utility of creating buildings or building components in a separate location (e.g., fab shop) designed within a controlled environment. Once the pieces are completed, a construction company will transport the materials to the job site for assembly and close-out for their owners. Prefabrication is essentially the process whereby structures are manufactured in a “fabrication shop” but installed on the jobsite.
Offsite construction is closely related to prefabrication but slightly different. It involves the broader aspect of planning and manufacturing buildings in another place and agnostic as to how the components produced are eventually assembled onsite. They may be modular, manufactured, or piecemeal. For instance, manufactured housing refers to homes built elsewhere and delivered to a site. Modular housing relates to fully assembled pieces of residential buildings manufactured offsite, then delivered for final placement and connection onsite. Prefabrication can refer to both of these and the manufacture of repeatable components (steel, timber frames or glass panels, for instance).
Prefabrication is growing in popularity, with many MEP Contractors jumping on board. Shapiro & Duncan’s fabrication shop, located in Landover, Maryland, has over 51,000 square feet outfitted with state-of-the-art workstations and hoisting equipment for cutting, fitting, and joining various types and sizes of pipe.
Prefab: What’s all the buzz
With much data being reporting about the impact of prefabrication, it’s much more than a passing trend or buzz. Across the U.S. and worldwide, prefabrication is growing at different stages along with modular construction.
ResearchandMarkets.com reports the global modular construction market is projected to grow from $91 billion in 2020 to $115 billion by 2025, at a CAGR of 5.7 percent as interest rises in the cost-effective construction method to help sustain growth. According to Fortune Business Insights, which reports similar financial growth projections, Modular building solutions are gaining popularity among builders because of their benefits, including reduced waste, speed building, cost-effectiveness, eco-friendliness, and flexibility. Industry experts also reported that modular and prefabrication projects had been completed 30% to 50% quicker than traditional construction. A major driver for the growth is attributed to increasing infrastructure activities caused by rapid urbanization. To bridge the gap between rising demand and supply, builders are adopting advanced manufacturing techniques such as prefabrication.
The commercial construction success of prefabrication is much more realized because of the repeating elements (e.g., piping, duct, plumbing, etc.) used on projects. Cost-cutting and time savings promises can make onsite assembly quicker, cheaper, easier, and better quality. The same goes for glass panes, which often make up a vast exterior surface area on skyscrapers, warehouses, and apartment buildings.
The traditional jobsite stick building method is not sustainable for companies looking to grow and compete. That’s where prefabrication comes in.
Prefabrication in Construction
In 2021, prefabrication is a broad term defining the practice of assembling structural components to manufacture and transport sub-assemblies to the construction jobsite. Prefabricated steel and concrete sections are repeatedly used several times to construct a building, so this repetition is a prime opportunity for applying a manufacturing process and cost-savings. The economies of scale present a lower cost per unit within a safer environment than the jobsite and require less labor. As scores of components are created and bulk transported on schedule, it saves on travel costs and mitigates poor weather impacts. Less labor is also needed on the jobsite to assemble pieces perfectly constructed versus build as needed. Data shows that the increased productivity from preparing a structure offsite then adding prefab pieces in large batches onsite is substantial.
The Benefits of Prefabrication
Prefabrication arguably reduces flexibility in the design of a building. However, the diminished flexibility is marginal, and the benefits to commercial projects, contractors, and their stakeholders are substantial. A few benefits include:
— Reducing Labor Risk: Contractors are already having difficulty finding labor, but construction still needs to happen. When onsite construction proceeds piecemeal, it reduces labor productivity even further, and mistakes are more prevalent. Therefore, prefabrication helps companies speed up timelines and increases productivity of the reduced labor required for the jobsite.
— Increased Safety: Prefab is often cited for reducing congestion on the jobsite and increasing safety due to the controlled and cleaner offsite environment (trip hazards like cords, 2×4’s, rebar, etc. that exist on the job site are not usually in the shop work areas).
— Cost-Savings: Labor productivity rises, and costs drop associated with moving components and units from the fab shop to the jobsite for assembly. The efficiencies gained from managing less-needed trade workers on the jobsite also increases safety and mitigates mistakes.
— Saving Time: Many reports and case studies indicate significant schedule savings attributed to prefabrication – bringing a substantial return on investment to all stakeholders, including the owner. This is essential in mitigating weather and other types of delays.
— Quality control: When compared to repeated construction onsite, factory tools can offer added quality assurance. Streamlined manufacturing and assembly processes also improve safety on the jobsite.
— Reducing environmental impact: A fab shop’s controlled environment enables a more accurate distribution of materials to the jobsite and reduces substantial waste.
These benefits drive enormous interest in prefabrication as a practice for streamlining construction projects, saving companies money, and driving further innovation in the field.
Trends Impacting Prefabrication
Right now, several trends show significant promise in enabling contractors to embrace prefabrication, three in particular.
Although not new technology, the first is BIM or building information modeling. This allows designers to visualize the whole lifecycle of a building, from groundbreaking to daily use. Prefabrication further enables designers, architects, and builders to understand the intent and use of any structure.
The “digital twin” is a virtual representation of a physical object. This technology is disrupting full product lifecycle management in construction, from design to manufacturing to service and operations. The physical manufacturing of objects is virtualized and represented as digital twin models and integrated into virtual and physical spaces. Digital twin technology enables fabrication shops to monitor model to actual comparisons to ensure that what is being built in the physical world matches what was designed in the virtual world.
Lean construction also plays nice with prefab to reduce time, materials, and labor through innovative technologies and strong communication between stakeholders and teams. Lean construction is paving the way toward a greener, more productive future. As prefab structures are inherently lean, we can all look forward to the possibilities brought about by their marriage.
Examples of Successful Modular Construction
Prefabrication is becoming a significant component of large construction projects. Major businesses and institutions are asking contractors to leverage its use and adoption. For example:
Google has been leveraging modular building techniques, grabbing this strategy for its future products due to its efficiency and cost-effectiveness. Their rationale? Google loves to innovate, and modular structures enable endless opportunities for redesigning their site over time.
Walmart Pharmacy Clinics in less than 60 days: Walmart Health has partnered with BLOX to standardize manufacturing processes to rapidly build new Walmart Health clinics across the U.S. Why is this important? It allows Walmart to accomplish more with less: faster, more efficient construction requiring fewer resources, allowing them to serve more customers quicker. This innovative collaboration allows Walmart to tailor the clinic’s design to meet the unique needs of the communities they serve while providing the necessary infrastructure to scale and continually improve the clinic model.
Yale has been an early user of prefabricated construction dating back to 2006. To provide temporary space during the construction of new campus buildings, the university employed modular spaces for the Political Science department. The result was room to teach and research while construction occurred, reducing disruption of academic life.
Have you been to Starbucks or McDonald’s? These firms have turned to their designers for creating small, intensive-use buildings that rely on pop-up construction methods to save time and money. They point toward a future in which cheap and easy solutions for living spaces, commercial buildings, and office buildings will abound.
Prefabrication’s possibilities are endless
Prefabrication’s possibilities are just beginning to be felt across the construction industry. From choosing by advantage – one or several aspects of a project to full adoption, MEP Contractors should be integrating prefabrication into almost every project to reap the benefits mentioned above and become more competitive.