Intro to Modular Construction
Does everything we build need to last forever?
- Modular construction is being implemented to speed up the construction of schools across the USA.
- This technique can cut a 9–15 month construction duration to just 12 days for a typical classroom.
- Modules can be reused and stacked into new arrangements, making future expansion or reconfiguration cheaper and easier than a complete rebuild.
- Engineering design can be automated with the repetitive nature of modular construction, leaving room for engineers to innovate new ideas.
The earliest evidence of human construction dates back to the Neolithic age between 9000 BC and 5000 BC. Humans built bridges out of wooden logs and used pit houses as shelter from the elements. Skara Brae, a UNESCO World Heritage Site, is a stone-built Neolithic settlement, located on the Bay of Skaill on the west coast of Mainland, the largest island in the Orkney archipelago of Scotland. It was occupied from roughly 3180 BC to about 2500 BC and still exists today. Pretty impressive right?
Now, fast forward to the 21st century, and the built environment consists of every type of infrastructure imaginable to suit humanity’s needs. In fact, there is such a surplus of buildings that some of them are abandoned, neglected, and eventually deteriorated. Humans built so much so fast that global construction waste is expected to reach over two-billion tons per year by 2025.
So what new innovation could remedy this issue?
Cue Modular Construction
By definition, “Modular construction is a process in which a building is constructed off-site, under controlled plant conditions, using the same materials and designing to the same codes and standards as conventionally built facilities — but in about half the time.”
Modular building can be compared to a popular childhood pastime: LEGO sets. The construction process involves transporting multiple prefabricated pieces (the “bricks”) which are built on-site to form a complete structure.
Concrete has excelled immensely in the modular space with the development and implementation of precast concrete in building construction for the last 50-plus years. Shifting focus, the idea that steel structures can be modular is starting to gain momentum.
How is it built?
The prefabricated sections are manufactured offsite and can be stacked in various configurations, such as end-to-end or stacked one on top of the other. Once the prefabricated modules have been placed, they’re assembled to form one cohesive structure. It’s like a LEGO build but human-sized.
If it becomes more widespread, modular construction could lead to exponential increases in efficiency in the building industry. The ease with which these structures can be disassembled and transported elsewhere for reuse is a sustainable practice that would reduce the amount of construction waste we produce globally. This idea isn’t new, but recent advancements in technology, economic demands, and alternative thinking are paving the way for renewed interest.
The Pros and Cons of Modular Buildings
Modular construction takes a significantly different approach to building. Because much of the process takes place at a manufacturer beforehand, projects can be completed in half the amount of time that traditional methods take, where construction begins and ends on-site. Factory-based manufacturing helps reduce delays from typical obstacles like storage, unpredictable weather, and vandalism.
Since prefabricated buildings use more lightweight materials that are cheaper than traditional building materials, they have the potential to deliver significant cost savings. This would create a greater return on investment for landowners and developers.
“In the European and U.S. markets alone, modular construction could lead to annual savings of up to $22 billion.”
A building specialist at iMod stated one of their school construction projects classrooms would typically take 9 to 15 months to construct out in the field. With modular construction, the classroom was built and assembled in just 12 days!
Perhaps most importantly, modular construction is more sustainable than traditional construction methods. Modular structures can be disassembled and relocated for a new structure, reducing the demand and producing energy for raw materials. Additionally, building in a factory helps eliminate waste. Inventory can be sized without waste, easily manufactured, and protected from damage that typically takes place in the field.
On the worker side having a primarily indoor construction environment leads to improved safety and fewer accidents for construction crews. It also results in improved air quality within the buildings themselves, as a factory-controlled setting eradicates the potential of moisture getting trapped within walls.
On the design side, having a modular structure means that the structural analysis would be very straightforward. If you know the only changing factor is loading, weather, and ground surface, then it should be fairly simple to automate the design process to incorporate the unknowns. This can change the way we utilize our engineers creating more space for them to innovate new technology to further design success.
A notable con of modular building is the lack of architectural character. In big cities all around the world, some of the most iconic buildings have sophisticated facade detailing. There is no room for complex design when everything is meant to be one of the same over and over. Fabricators do argue that the structure itself can still be made aesthetically pleasing though.
Another disadvantage of modular construction is size limitations. The only means of transportation is a truck which means the modular section cannot exceed the largest truck bed size. Companies like iMod have worked to perfect their modular structures to fit truck beds, cranes, cargo ships, and more.
Additionally, creativity and flexibility are a bit strained (don’t show the architects!) But seriously, making alterations to any MEPs locations for example could drastically change the usability of the modular structure. It is prefabricated to handle all necessary penetrations to be structurally sound and functional, but this leaves little to no room for customization. It is tethered to certain types of straightforward facilities such as schools, warehouses, medical offices, etc. There will be no abstract anything in modular construction.
For a brief intro to the latest developments in modular construction, I highly recommend watching the linked video above. Modular buildings are a step in the right direction when it comes to improving efficiency, building sustainably, and reducing waste in the long run!
