Conjuring up images of the Star Trek Replicator, NASA has announced that it is studying and developing 3-D printing technology for space exploration and construction. Recently, astronauts on the International Space Station printed a 3-D wrench based on designs “beamed up” from Earth. However, that is only the tip of the iceberg: NASA also is reportedly examining the use of 3-D printing in applications such as rocket parts, robotic landers, and even building structures on the moon and Mars.

Here on Earth, developers are exploring methods to extrude and print building components layer by layer using additive 3-D printing technology. The advantages of such processes include flexibility to design hard-to-build structures, potential for mass customization, lower forming and tooling costs, and substantially lower labor costs.

Many design firms already use 3-D printing technology to create models, but several entities have announced innovations that tout fully printed construction components. For instance, the England-based engineering firm Arup announced the ability to print steel structural elements for use in complex projects. Contour Crafting in the United States and WinSun in China claim the ability to print complete concrete structures in a single day. Such applications range from printing building shells and components that can accept mechanical, reinforcement and electrical installations to printing multi-story structures.

Experts warn that it remains unclear whether solutions exist that would truly allow for the commercialization of multiple-material printing methods, and that would meet the structural, time, material properties, surface finish, cost and other requirements for full-scale building.

“Advances in concrete materials technology will be required before 3-D printing technology can be widely applied in the building and infrastructure sectors,” says Timothy Tonyan, senior vice president of global engineering consultant CTLGroup. “Concrete mixtures that possess the necessary flow and stiffness at time of placement, combined with the necessary structural characteristics and long-term durability when cured, have yet to be developed.”  

The idea that buildings can be “printed” with relatively minimal labor is intoxicating and has attracted the attention of many engineering and construction leaders. But with any new technological advancement, there are practical and legal issues to consider.

A Substantial Intellectual Property Landscape
Various patents are already in place or pending for certain 3-D printing technologies, but opportunities may exist to the extent that certain patents have expired or will soon expire. It will be important to see whether intellectual property disputes and litigation ensue as new 3-D printing technology announcements and claims surface.

Building Code Concerns
Concerns related to the long-term durability of 3-D printed concrete structures—plus energy efficiency, fire performance, acoustical characteristics and sustainability—will require testing to establish performance criteria.

“3-D printing with concrete can be used to create aesthetically exciting, complex building components and structures using new composite concrete materials,” Tonyan says. “Current approaches to code evaluation rely on the use of established design methodologies applied to standardized structural shapes built with traditional materials. Material requirements and structural design parameters for 3-D printed concrete structures have not yet been established by the building research and design community. As a result, new approaches for characterizing, testing and validating material properties and new structural design parameters will need to be developed to enable 3-D printed enclosures to be appropriately evaluated from a building code perspective.” 

Potential Challenges to Traditional Construction Roles
3-D printing has the potential to increase productivity, but decrease traditional construction roles. Jobs for craft professionals to finish surfaces, erect formwork, pour concrete, finish surfaces and perform other tasks may be eliminated. Trades such as crane operators may have to learn new skills for erecting, operating and dismantling the 3-D printers and gantries. This hurdle could impact locations where 3-D printing technology is first employed in the construction sector.

When Will Insurers and Underwriters Accept the Technology?
Insurers may try to claim 3-D printed materials constitute a material change in risk under current applications and policies. It’s also unknown whether 3-D designers and erectors will need product liability coverage or entirely new forms of professional insurance or general liability insurance coverage. Close communications with insurers and brokers may be warranted.

Potential Transformation of Longstanding Construction Law
To the extent that printed building components could be considered goods rather than services, it is possible that disputes regarding 3-D designs and printed structures may need to be resolved under the law of sale of goods (under Article Two of the Uniform Commercial Code) rather than under traditional construction law principles currently applied to construction and design services contracts. Such a development could have outcome-

determinative consequences for disputes involving the formation of contracts, the imposition and disclaimer of warranties, causation of loss, damages calculations, and termination of contracts and statutes of limitations.

For instance, if a contractor merely sets up, operates and dismantles a printer, would that contract fall under “the sale of goods?” To what extent does adding design or other erection services to the contractor’s work affect the analysis? Or, what if 3-D printing is used to remotely or robotically “print” buildings in hostile environments, such as undersea structures, waste sites or structures that bridge chasms? If a general contractor can print an entire building using multiple materials and complex structures and designs, would the design component be treated under one analysis, but the erection component under another?

3-D printing is here to stay in the engineering and construction industry. However, key concerns linger around whether solutions will be developed to allow the technology to be used for complex construction itself, and if the economics, ownership rights, and legal and insurance risks will be resolved so that the technology can be commercialized. This is a transformational time in the construction industry, so it’s crucial that companies begin to prepare for the legal and practical challenges associated with 3-D now.

Josh M. Leavitt is a principal and co-chair of the construction law practice at Chicago-based Much Shelist, and is an elected fellow of the American College of Construction Lawyers. For more information, call (312) 521-2627 or email