There’s a huge housing supply gap: the United States needs an estimated 3.8 million single-family homes and 325,000 multifamily housing units a year to catch up with existing demand. Meanwhile, the construction industry is facing a shortage of skilled labor and pressure to be less resource intensive. To many builders, technology looks like the answer.
“We need to reach for another construction method, using the tools and techniques from advanced manufacturing, and bring more tools to the toolbox for the modern-day construction workforce,” says Tom Woodman, executive director of Citizen Robotics, a nonprofit that educates communities about 3D printed homes.
“Robotics” may call to mind science fiction images, but robotics in construction does not mean humanoids climbing ladders and swinging hammers. It mostly means employing automation to do a range of work, primarily off-site (except for 3D printing), in a standardized fashion. Robots might pour a foundation, cut lumber, assemble wall panels, install screws and nails, or be heavily employed in building modular parts of a building that can be assembled on-site.
While affordable housing developers have so far struggled to achieve the scale necessary to achieve cost savings with these methods, they are being adopted in places throughout the broader construction sector, and their proponents argue that their speed and precision can make a notable difference in housing costs.
With robotic manufacturing, “costs are more predictable, schedules are more predictable, we can use repetitive processes where possible, and then we can actually start to bring down the cost,” says Ramtin Attar, co-founder and CEO of Promise Robotics, a technology startup that develops robotic systems for use in panelized construction, which is when the structural components of a building (walls, floors, and roof) are constructed off-site and delivered to the job site for erection.
“Robotics is ultimately just an enabling technology with great potential to change the economics of [the] construction business,” says Attar. “New technology like robotic systems open new possibilities to rethink some of the existing relationships in the supply chain, upskill the workforce, train an entirely new generation, lower the barrier to tech adoption, and break the cyclical nature of the business.”
The Need for Workers and the Rise of Robotics
ABB Robotics conducted a survey in early 2021 about the use of robotics in the construction industry. It asked 1,900 construction or construction-related businesses in North America and Europe and in China about the need for workers and their use of robotics.
Overwhelmingly, respondents felt the industry was headed toward a skills crisis by 2030. This is easy to see when you consider that there were over 311,000 construction vacancies in the U.S. in the second quarter of 2020, and 200,000 in the European Union in the same time period. Over 40 percent of respondents struggled to recruit workers.
When asked if they were looking into using robotics in the next 10 years, 81 percent said yes. Some have already begun the journey, with 55 percent saying they use robots currently.
What are some of the top benefits of using robotics in homebuilding, according to proponents?
1. Fewer Errors, Less Waste
As much as 30 percent of all building materials delivered to a typical construction site can end up as waste. In part, that is because humans are imperfect and constantly make mistakes and errors. A PlanGrid and FMI Corp. survey of 600 construction leaders projected that $177.5 billion would be spent in 2018 by companies throughout the industry fixing mistakes, looking for project data, and managing conflicts. These errors can be caused by poor design, inaccurate data, bad communication, and human error. This leads to wasted materials and time, as workers must redo what’s been done incorrectly, to the tune of up to $31.3 billion in 2018.
The use of robots cuts down on the amount of materials being thrown away, largely through reduced errors. Robots follow the programming they’ve been given. There’s no deviation from the information and cuts are precise. If the programming, maintenance, and operation is correct (a big caveat), a robot’s performance will be perfect.
Off-site construction also makes it easier to redirect scraps to other projects when they are using the same materials, since they do not have to be collected, stored, and transported elsewhere.
The reduction caused by not having to order as much material eventually leads to lower costs, as contractors pay for less material that they don’t use.
2. Less Labor Needed
Crews of carpenters are often fairly large in size, depending on the project. With robotics, fewer workers are needed on site and crew sizes can be smaller. “If you’re going to build, say a 1,500-square-foot home, instead of having 12 guys on site for two weeks to do the framing, 3D printing is two people and a robot for three or four days to extrude all of those walls,” says Woodman of Citizen Robotics.
Being able to use smaller crews can save contractors money with lower labor costs. Some of those costs are offset by the cost of the robot and necessary maintenance. But over time the crew savings will pay for those added costs. As the example above discussing 3D printing shows, for certain portions of a job, there can be a labor savings as high as 94 percent. Because of design differences across projects and the higher upfront cost of the machines, however, it’s hard to make apples-to-apples cost comparisons.
3. Fewer Delays
As construction moves more off-site, external forces like weather create less of an effect on project schedules. With modular construction, some or all of the components can be built inside a warehouse, which is climate controlled and protected from weather. This protection allows work to continue during storms and other weather events that might delay construction normally. It also prevents damage to the building during construction.
4. Improved Safety
Robots are able to handle heavier loads, work in dangerous spaces (like under slabs and in tight places), and perform repetitive or dangerous tasks much easier than humans. This leaves lighter tasks to human power, making construction safer for everyone. In the ABB survey, 34 precent of respondents thought robotics and automation could make work safer.
“Walls, ceilings, or floors, that’s where all the heavy materials are, and there’s a lot of lifting and moving around that’s really not good for the person doing it,” says Rick Murdock, co-founder and CEO of Autovol, a contractor that uses robots to build modular components that they assemble and connect on site. “Our robots pick up all that weight. They don’t care how much it weighs.”
- A More Diverse Workforce
Autovol has brought in several younger workers as robot operators, and it is increasing the number of women it employs. “Today our plant’s 33 percent female,” says Murdock. “A large part of that is due to the automation processes.” Because robots are doing all the heavy lifting, upper body strength is not as important in hiring, which may allow women, who are underrepresented in the traditional construction workforce, to feel more comfortable seeking those jobs.
Of course, there are also challenges to using robots in construction.
Challenges of Using Robotics in Construction
1. Lack of Critical Mass
The use of robots in construction is still fairly new, less than 10 years old. Although some early adopters have been doing it longer, it certainly hasn’t hit the mainstream industry yet. In fact, in the ABB survey, one-third of companies said that robots were not compatible with their work.
However, until there is more widespread acceptance of robots and their use, it will remain difficult to get production to scale, which limits their usefulness.
2. Lack of Workers with Needed Skills
The type of workers needed when robots are being used for construction is quite different from traditional carpenters and laborers. Instead, workers on site are robot operators, software developers, engineers, and technical troubleshooters. This means the workforce the industry recruits must change. With the increased use of robotics, college degrees may become necessary to get into the industry.
3. Need for Standardized Design
Current buildings are designed to create a unique look that sets them apart from other buildings. This uniqueness is the hallmark of every building’s design. With robotics and other technology assisting the construction process, “you must think in terms of software, modularity, and computational design,” says Andrea Cassoni, managing director of Business Line General Industry with ABB. Programming something new every time reduces the time (and possibly materials) savings of automation.
There are also limits on what designs are practical. Currently buildings are designed and then we figure out how to build them. With robot technology the design must be informed by the abilities of the robots. If robots and printers can only handle one type of material, for example, then the design needs to use that one material.
And all the construction drawings must be 100 percent complete. “You can’t leave anything out because a robot doesn’t know. All he knows is what he’s programmed to do, and he can’t think for himself,” says Murdock.
“When we design something for robotic manufacturing, much more engineering and design work needs to be completed upfront,” says Attar of Promise Robotics. “By the time we are done with our manufacturing digital model, we know the location of every stud, hole, nailing pattern, screw, and staple.” It’s possible this could increase cost on the design side.
Looking to the Future
The companies that were contacted for this article see no problem scaling up their operations when the time comes. The demand is there, and they are working diligently to build a supply. Most see the only barrier to growth as the adoption of the technology. As robots are seen less as an anomaly and more just how things are done, there will be more demand for their work.
“When you go meet with people in other industries that are using robotics—health care, automotive, logistics—they’re just amazed that construction industry has not adopted robotics yet,” says Attar. “It makes so much sense that people become skeptical. It’s like, ‘why hasn’t this happened?’”