The modular construction market has experienced a massive surge of growth over the past few years, reaching a value of $76 billion in 2021.
While modular construction currently represents a small subset of the $1 trillion construction industry, the market will only continue to grow as demand increases. More people than ever are turning to prefabrication for its on-site efficiency, improved labor productivity and safety and lower construction costs.
In addition to these benefits, modular construction represents a huge leap forward in environmental sustainability, including excellent opportunities for more responsible use of building materials and more eco-friendly designs.
Read on to learn more about the benefits of modular construction and how it works, or jump to our infographic to get a visual look at the eco-friendly features of modular buildings.
What Is Modular Construction?
Modular construction is a process that involves constructing prefabricated buildings in off-site factories and transporting them to a worksite for installation. While modular structures meet the same building codes and regulations as traditional buildings, they consist of smaller prefabricated units, called modules, which are assembled after arriving at a worksite.
- In the factory, modules are built using assembly line systems and construction technology, leading to an efficient and standard process. The use of precise modeling and construction in the factory reduces the need for change orders and adjustments.
- Before leaving the factory, walls, floors, roofs, doors and windows are built and installed, and wiring, plumbing and ductwork are added. Many modern modular buildings are even outfitted with fixtures and finishes before leaving the factory.
- Once the modules are built, they are transported to the building site on flatbed trucks and assembled in a predetermined order, a process that uses cranes to set the modules in place onto a preset foundation.
- After the modules are set in place, construction professionals seamlessly fit them together to create a unified building. The resulting structures are often finished twice as fast as similar buildings on traditional sites.
Types of Modular Buildings
There are two common types of modular buildings: permanent and relocatable. While both types consist of prefabricated materials built off-site, they differ in size and application and each serves a distinct purpose.
Permanent modular construction (PMC) involves building prefabricated modules off-site, delivering them to the worksite and assembling them to create a permanent structure. These buildings are highly customizable and come in many shapes and sizes. Professionals can use PMC to build anything from single-story homes to residential high rises.
Relocatable modular buildings are unique in that they can be moved from one location to another after the initial installation. Professionals either partially or fully assemble these structures in an off-site facility, then transport them to the building site. Because relocatable buildings are cost-efficient and easy to move or repurpose, they’re a popular option for construction-site offices, schools, medical facilities and other organizations that need a temporary structure.
Benefits of Modular Construction
Not only do modular buildings take less time to build, but they also offer many other advantages to construction crews, building owners and the environment. These benefits begin in the factory and continue throughout a building’s lifetime.
1. Decreases Construction Waste
Traditional building methods generate around 56 million tons of debris every year, while modular construction uses precise planning and measurements to reduce the risk of mistakes and wasted materials. Multiple modules are also created simultaneously during this process, so any materials that would otherwise be discarded can be reused for other projects in the same facility.
2. Uses Recycled Materials
Modular buildings use a variety of sustainable materials, many of which are recycled. Repurposed materials like wood, steel and aluminum can form siding, frames and roofs. Some modular construction companies also use innovative materials like oriented strand board (OSB) made from fast-growing, sustainably sourced wood. Modular design professionals are getting increasingly creative with sustainable materials in their buildings. For example, Wikkelhouses are made entirely of recycled cardboard and are expected to last for 100 years.
3. Decreases Energy Consumption
Since construction happens in a controlled factory setting, producing a modular structure uses less energy. During construction, energy usage is optimized using machine learning to create an environmentally sound building process, and shorter construction times result in lower on-site energy expenditures. Professionals can also install structural insulated panels in modular buildings to better maintain their internal temperature and reduce the need for heating and air conditioning.
4. Reduces Emissions
A United Nations report from 2017 found that 39% of global carbon emissions result from the construction field, much of which results from inefficient material and labor transportation. By reducing trips to and from the job site and optimizing module delivery, modular construction can reduce total deliveries to building sites by 90%, which greatly reduces total emissions. Additionally, many modular buildings are equipped with solar panels to lower carbon emissions for the lifetime of the building. A simple solar setup can prevent 2.5 tons of carbon emissions annually.
5. Features Green Fixtures and Finishes
Modern modular designs include a slew of eco-focused features, like dimmable LED lighting, solar water heaters, occupancy sensors, batteries for energy storage, triple-paned windows and electric carports. Innovative companies like Plant Prefab put environmentally sustainable features first, using materials with no volatile organic compounds (VOCs) and natural airflow technology to create healthier designs for humans and the planet.
6. Built To Last — And Be Reused
Modular building designs have a distinct advantage when it comes to resilience and long life spans, but this can also be true of many traditional buildings. Unique to modular buildings is the ease with which they can be disassembled — to be either reused in other locations and configurations or recycled for new projects. When considering long-term sustainability, reusable modular buildings help reduce debris generated by demolition, which accounts for more than 500 million tons of waste each year.
7. Improves Worker Safety
Because much of the building process takes place indoors in a controlled environment, modular construction greatly reduces the risk of falls and other work-related injuries. This is an important advantage in an industry plagued by high work injury and mortality rates. Less on-site work protects workers from dangerous weather conditions, eliminates hazards and lowers the risk of fatigue.
8. Lowers Project Costs
Shorter construction times, fewer transportation and labor costs and less expensive materials make modular construction more cost-effective than traditional building methods. As technology continues to advance and the process becomes more efficient, project owners may even see further opportunities to reduce costs in the future.
What Are the Drawbacks?
While modular construction offers many benefits, it isn’t without its drawbacks. It’s important for anyone considering this building method to consider the following challenges carefully.
1. Risk of Damage During Transport
Because modules — and sometimes entire structures — are built off-site, there is a heightened risk of damage as they are transported to the construction site. Project owners must carefully choose a trustworthy rigging company to help reduce the risk and avoid project delays caused by damaged modules.
2. Limited Design Options
Modular buildings are fast and efficient to build, but they often have fewer customization options than traditional structures. Construction professionals stack repetitive and uniform modules to build structures like apartment buildings, hotels and homes. Creating more unique modules would require much more time, money and resources, eliminating many of the benefits of modular construction.
3. High Upfront Costs
Because modular construction comes with many upfront material and labor costs, project owners must be prepared to pay more upfront for a modular building than they would for a traditional one. An accelerated payment timeline can make working with investors who aren’t used to the process more difficult and leave less room for error.
4. Fewer Suppliers
Working with fewer suppliers may sound like a good thing, but it can place more pressure on the buyer to choose a trustworthy company. One building project may only require one modular manufacturer, and there aren’t always many options to choose from in the still-growing market. Because so much of a project’s budget goes to one supplier, it’s vital that buyers carefully examine all of their options and follow up as the project progresses.
The Future of Modular Construction
Prefabrication allows for quicker and more cost-effective building processes, which could help alleviate the current affordable housing crisis. The efficiency of modular construction could be necessary as construction sites adapt to industry changes in the wake of the coronavirus pandemic.
Modular construction technology is a powerful remedy for many challenges facing today’s construction industry, like high costs and labor shortages. Importantly, though, modular construction also has a beneficial effect on the environmental impacts of construction and encourages building designs that utilize green energy for a more sustainable future.
Overall, modular construction technology could be a vital source of change in the industry — especially for our impact on the planet — in the coming years. To learn more about the environmental benefits of modular construction, check out the infographic below.