In modularized construction, buildings and other infrastructure are manufactured off-site in a controlled workshop environment. ‘Modules’ are then transported to site, installed and connected to essential services. Modular projects can be built using the exact same materials as traditional construction, in line with the exact same building codes and standards. Or, construction occurring offsite may result in being able to access or utilise different materials that may have been more difficult to utilise in the field.
Modular construction can accelerate construction speed by as much as 50% and cut costs by as much as 20%. Modular construction could claim US$130 billion of the construction market in the US and Europe by 2030, delivering annual cost savings of US$22 billion.
While modularization is often utilized on remote work sites, the significant benefits it offers makes it attractive to even the most accessible of projects.
The Benefits of Modularized Construction
Modularized construction offers a range of benefits, particularly when compared to traditional construction methodologies. This is especially true when optimized and delivered in conjunction with BIM and digital engineering.
Accelerated Construction Schedules
Recent modularized construction projects have accelerated project timelines by as much as 50%. Lean offsite manufacturing in a controlled workshop environment is much faster than traditional on-site construction. In a workshop, automation and robotics can be used to increase throughput. Factors like inclement weather are eradicated, along with their associated delays.
Manufacturing in a workshop can also occur in tandem with early site works, such as civil excavations and the pouring of foundations, compressing the overall construction schedule.
Once modules are delivered to site, they can be assembled quickly and easily. On average, a team of five workers can assemble 270 square meters of finished floor area per day—significantly faster than traditional construction.
Enhanced Build Quality
Modularized buildings are built in accordance with the same building codes and regulations as traditional construction projects.
However, quality control in a workshop environment is facilitated much more easily than on-site. This is particularly true when automation and robotics are employed — processes are easily repeatable and computer controlled for precise results. This eliminates or significantly reduces defects, clashes and the need for rework, resulting in better overall build quality.
Controlled environments, such as within a fabrication workshop, allow for faster, safer, higher quality processes too. This is not just because of robotics but also because other environmental factors can be controlled, such as temperatures and safe access to equipment, such as overhead cranes.
Improved Risk Management
With fewer defects and less rework, other benefits emerge. Material waste is significantly reduced. Delays due to slow shipments of additional materials are all but eliminated. In a workshop, material can also be carefully monitored via inventory control measures.
Approximately 80% of traditional labour can be moved off-site, into a workshop. With controlled workshop environments posing fewer safety risks than building sites, modularized construction can also improve worker safety.
As a result of all these benefits, the usual risk associated with construction projects for asset owners, developers and governments can be all but eliminated.
Improved Environmental Impacts
As mentioned, the workshop-controlled modularization process generates less material waste, improving the environmental impact of a project. It can also help to improve air quality, with warehouse emissions more easily controlled than in traditional open air construction. Plus, modular buildings are exceptionally flexible; they can be disassembled and relocated or easily refurbished, reducing the demand for raw materials and energy consumption that new buildings command.
Alleviated Skilled Labor Shortages
Many nations are currently facing a shortage of skilled labour. This challenge is particularly prominent in Hong Kong, Singapore, Australia, the United Kingdom and some parts of the United States. Modularization can help alleviate this issue in two ways. As mentioned, approximately 80% of traditional labour can be moved off-site, into a workshop. Some of the work usually completed on-site by the most skill-intensive trades can be handled by non-trade qualified manufacturing workers.
Alternatively, off-site fabrication can be undertaken in a location where skilled resources available. For example, Hong Kong is currently experiencing a skills shortage. So, rather than rely on traditional on-site construction, building can be modularized in a place like China where skilled resources are available. Skilled resources do not have to be located in the vicinity of the project.
Reduced Building Costs
It is estimated that modular construction in Europe and the United States could deliver annual savings of up to US$22 billion. It is estimated that modularization should save construction projects up to 20%.
With reduced construction schedules, costs associated with site overheads (like security and inclement weather) are reduced. Plus, buildings can be occupied sooner, resulting in a faster return on investment for asset owners. With fewer defects and less rework, material costs are lower. Labour costs can also be reduced by as much as 25%
Modular Construction Benefits in Action
Oxagon: A Reimagined Industrial City in Saudi Arabia
Part of the Neom project, Oxagon is a brand new manufacturing city in Saudi Arabia. Oxagon will be built largely using modular construction methodology. Approximately 90% of all components will be prefabricated to cut waste and reduce carbon in built structures by up to 60%. Oxagon is also being set up to facilitate modular fabrication and manufacturing.
Oxagon will harness that power of a full digital twin model that enables prototyping before construction. Any manufacturer will be able to input their technology into the model, allowing for simulation of benefits and trade-offs, and design optimization.
Other Neom cities, such as Trojena and The Line will also heavily rely on modular construction. The need for modularization in each of these locations differs enormously, but the benefits are clear. Trojena, for example, poses a difficult environmental—modularization allows for easier transportation and logistics, with minimal impact on its mountain location. The Line needs to be built as quickly as possible — modularization enables rapid construction. As a floating city that may need to be reconfigured in the future, the buildings on Oxagon has to be flexible and easily disassembled and reassembled — again, modularization is the answer.
Light Public Housing in Hong Kong
Hong Kong is looking to transition some of its site-based construction projects into offsite Modular Integrated Construction (MiC) facilities to allow for more efficient and cost effective construction.
The Hong Kong Housing Bureau is currently implementing an aggressive residential construction campaign to meet the growing population requirements. Eight sites have been selected across Hong Kong for the construction of approximately 30,000 light public housing units. By employing modularized construction, this public housing program is being rapidly accelerated. The construction period is expected to take just one to two years, with the first batch of approximately 2,100 units due for completion in 2024-2025, and the remaining units delivered in the following two years.
Modular construction is helping Hong Kong to overcome several challenges faced in recent years, including a shortage of skilled labor, high construction costs and demand for better safety, quality, and environmental sustainability.
How to Apply Modularization
Modularization can be applied to any type of project—whether it’s a space constrained apartment building in the middle of Hong Kong, a new city in the mountains of Saudi Arabia, or a remote mine site in outback Australia. There are two key aspects to the modularization process: early planning and effective collaboration.
It is essential that modularization is considered as early as possible in the planning phase. Project stakeholders need to analyse factors like high risk trades and potential risks to scheduling. Where construction can be modularized, with work fabricated offsite to mitigate risks, this should be considered. Modularization cannot be an after-thought.
Multi-disciplinary collaboration and communication is essential for effective modularization. All construction disciplines, from fabricators and steel fixers, through to contractors, electricians and plumbers need to be involved in the planning phase. Modularization must consider all construction disciplines and must be effective and beneficial for all.
With modular construction proven to accelerate construction speed by as much as 50% and cut costs by as much as 20%, its benefits cannot be denied. Most importantly, these benefits are not applicable to just remote sites like mines in outback Australia, or tightly space constrained sites in major capital cities. With early planning and effective stakeholder collaboration, modularization can be applied to any type of construction project to mitigate risks like worker safety, labor shortages, schedule slippage, material waste, environmental damage and poor-quality construction.