Prefabricated Modular Building

As every professional in the building industry knows, construction can be a costly and endlessly time-consuming endeavor. Delays are almost more frequent than on-time construction, and can be induced by extensive bureaucratic requirements, weather and other unexpected circumstances, inadequate planning, too few personnel, or a whole host of other causes. Lengthy construction projects can also negatively impact public perception of a project even before it has been built, especially if the projects experience delays or inconvenience those who live or work close to the building site. Moreover, some projects simply need to be built along a faster timeline than is typically feasible for a traditional construction project. Thankfully, there exists a solution for those seeking to drastically reduce construction times: modular construction.

Prefabrication in the Modern Era

In more recent times, the mid-20th century witnessed a surge in the use of prefabrication and modular construction methods. After World War II, there was a pressing need for housing and infrastructure. Prefabricated building systems, such as panelized construction, emerged as a solution to rapidly meet these demands. Entire wall panels, floor sections, and roof trusses were fabricated off-site in factories and then transported to the construction site for assembly.

Benefits of Prefabrication and Modular Construction

Enhanced Efficiency: MMCs enable simultaneous construction activities to take place, reducing project timelines significantly. Since components are fabricated off-site, weather conditions and site constraints have less impact on the construction process. The controlled manufacturing environment ensures better quality control and eliminates the need for rework in most circumstances.

‘On average, off-site manufacturing reduces construction time on-site by 30%. Latest ONS figures show just over 175,000 homes were completed across England in 2019/20, well below the government target of 300,000. If Modular Construction had been used and we assumed a 30% reduction in time on site, we could theoretically expect completions to be closer to 250,000, a net addition of 75,000 homes.’

Cost-effectiveness: Off-site manufacturing can lead to cost savings in various aspects. With off-site manufacturing, labor costs are reduced. Construction schedules are compressed, leading to lower financing costs (prelims). Additionally, prefabrication minimizes waste generation, optimizing material usage and reducing disposal expenses.

Sustainability: Prefabricated and modular construction methods are inherently more sustainable compared to traditional practices. The controlled manufacturing environment allows for better utilization of materials, reducing waste. Moreover, the off-site construction process generates fewer disturbances to the environment and nearby communities. Modular and prefab also allows for easy integration of sustainable technologies, such as energy-efficient insulation, solar panels, and rainwater harvesting systems.

According to the Engineering and Technology Editorial ‘two developments, which were built in London, achieved embodied carbon savings of 41 and 45% respectively when compared to traditional construction.’

Design Flexibility: Prefabrication does not limit architectural creativity. In fact, it provides design flexibility as building components can be customized to meet specific project requirements. The use of advanced Computer-Aided Design (CAD) and Building Information Modelling (BIM) technologies enables precise detailing and coordination between different components.

Challenges of Prefabrication and Modular Construction

Transportation and Logistics: The transportation of large, prefabricated components from the manufacturing facility to the construction site can pose logistical challenges. Roads, bridges, and infrastructure must be capable of accommodating oversized loads. Careful planning and coordination are required to ensure timely and safe delivery. There is also the issue of factory and site storage with modular – this is due to the modules large nature and problems faced with on-site assembly; for instance, the wind levels must be extremely low in order to crane the modules into position. As a result of prohibiting weather conditions, the modules must maintain a place of storage preferably proximate to the site location before they can be assembled.
Limited Site Adaptability: While prefabrication allows for design flexibility, there may be limitations when it comes to on-site adaptations. Once components are manufactured, changes to the design or layout become more challenging and costly. Detailed planning and coordination between architects, engineers, and manufacturers are crucial to overcome this challenge.

Skilled Labor Shortage: The shift to prefabrication and modular construction methods requires a skilled labor force with expertise in manufacturing and assembly processes. However, there is currently a shortage of skilled workers in these areas. Training programs and initiatives to attract and develop talent are essential for the successful implementation of prefabrication methods, however are in short supply.

The Future of Prefabrication and Modular Construction

There are a vast collection of factors - of which point to the future of UK construction being Modern Methods of Construction (Modular and Prefabrication) as opposed to our currently favored ‘Traditional’ methods of construction; steel frame and brick and mortar builds mainly - these historically proving to be very waste and carbon inefficient.

In Mark Farmer’s article ‘Modernize or Die’ the factors mentioned earlier, steering UK construction towards MMCs also highlight the failure of the UK Construction Industry in recent years. These factors consist of:

Lack of innovation
Not enough well-trained workers
Serious productivity losses
Lack of collaboration and improvement in culture

Referring to these factors, it seems as though all the benefits of modular and prefabrication construction relate directly, showing promise for the future. Innovation; the development of off-site manufacturing technologies and processes has improved dramatically over the last few years as more businesses have recognized the success potential. Labor shortage and productivity; factory production of prefab components eliminates logistical issues of sourcing all the different trades and bringing them to site as well as this productivity improves due to the use of efficient building techniques and technologies. Culture; MMCs also display and promote a more collaborative, environmentally conscious attitude to construction – a contrast to the culture that is widely adopted within the industry currently.

Conclusion

Overall, it can be deduced that MMCs have great prospects for construction, however they are not a definitive alternative to traditional builds, more so a substitute. Modular and prefab construction are a sector that needs to be pushed and facilitated more within the market as the majority of people are unaware of their advantages. Currently there is little to no difference in cost between modular/prefab and traditional builds therefore the popularity/demand is not where it should be due to the lack of incentive – this is something we need to change within the construction industry as a collective.

PRAPHULL RAMDAS WANARE