3D construction printing gets ready for its moment in the spotlight

The idea of using an “additive” approach in construction is not new. In fact, the first 3D printed building – a small, circular outbuilding made with stacked rings of extruded concrete—was erected in Indiana over 85 years ago. Back then, the inventor had three goals: to reduce reliance on labor, speed up time to completion, and decrease the cost and waste of materials. 

Those same objectives are driving the adoption of modern 3D printing techniques today. The global 3D printing construction market size in 2023 was valued at $7.6 billion, and the sector is expected to grow to over $296 billion by the year 2031, according to Insight Ace Analytic.

Could 3D construction printing (3DCP) lead the next wave of transformation in construction? Before embracing the technology, it is important to understand how construction projects incorporating 3D printing differ from traditional approaches, as well as the technology’s benefits and challenges. 

What is old is new again

In the past 85 years, technology behind 3D printing has gotten far more sophisticated than a “wall building machine.” Today, 3DCP encompasses multiple methods, including powder bonding, additive welding, and variations on the original extrusion approach that use wax, foam and polymers in addition to concrete.

The one thing that all of these methods have in common is that they use specialized equipment to automatically create all or part of a structure, on-site, from a single material. This differs from the traditional approach of combining various materials like steel, bricks and concrete to piece together a building section by section or floor by floor.

Lower labor, material and energy costs

The cost of labor to run a 3D printer typically amounts to half of total project costs, according to Autodesk, so reducing the number of workers required to complete a project can save a substantial amount of money. Meanwhile, speeding up time to completion amplifies those savings. In one example cited by the World Economic Forum, the on-site printers used in a residential project by Lennar required just three workers per home and completed each home three times faster than if traditional construction methods had been used.

Aside from labor, the other major component in the cost of a project is material. By using only the amount of material needed to complete the structure, 3DCP greatly reduces material waste, making this approach more sustainable. In addition, 3DCP equipment can be used with geopolymer concrete, which significantly reduces embodied carbon compared to ordinary Portland cement.

Finally, improved quality control and consistency during construction can lead to reduced energy consumption in 3DCP projects. Building performance may also be enhanced by making it easier to incorporate optimized designs for thermal insulation and structural efficiency.

With all these benefits, why isn’t 3DCP ubiquitous? As with any technology still in its relative infancy, there are challenges with 3DCP that developers need to consider before adopting it.

Lack of traction in larger buildings

The biggest issue holding back 3DCP is evident in where it’s made significant inroads: residential construction. Just as in a tabletop 3D printer, 3DCP equipment utilizes a gantry and scaffolding system affixed to a frame. The additive application of the base material is limited to the area reachable from this frame.

For this reason, 3DCP has taken off in residential projects that have a smaller footprint, like houses and low-rise apartment buildings. Where 3DCP has been deployed for larger buildings, it’s been limited to fabricating less-complex parts of the structure, like the rectangular walls of a warehouse.

Another reason 3DCP has yet to gain real traction outside of residential projects is that regulations and building codes for small residential buildings are typically less restrictive than they are for commercial ones. This has made it easier for residential stakeholders to embrace 3DCP techniques.

Quality and durability in question

There’s also a contradiction in 3DCP when it comes to quality and durability. On one hand, the special mix of concrete used in some methods resists the kind of slumping that can occur in wet concrete. On the other, that trait can make it more prone to chipping once dry.

But this is one issue that industry innovators are already addressing; recent advances in 3DCP include improved material formulations for better strength and durability. Solutions have also emerged that enable the incorporation of reinforcement methods, such as rebar, into the 3D printing process.

The up-front commitment

Answering questions of cost and ROI in adopting 3DCP can also be challenging. While labor and material costs can be greatly reduced, it’s also true that 3DCP requires a level of pre-construction setup that’s not present in traditional construction.

Developers considering 3DCP for their projects also need to keep in mind that innovative approaches often promise big benefits, but those rewards can be elusive for early adopters, at least in the beginning. Maximizing the advantages of 3DCP will take time, a growing body of know-how, and repetition, on top of a substantial up-front monetary investment. That investment will also have to include increased time and effort in potentially integrating 3DCP with existing construction processes and, for construction and design firms, workforce training and skill development.

The future, now in 3D

The methods, equipment, technology and materials used in 3DCP have come a long way since 1939, but the objectives of reduced cost and time and increased sustainability remain the same. The approach is already delivering on those goals in some cases, but there are challenges that need to be addressed before 3DCP can make a serious run at transforming construction.

Fortunately, the sector is a hotbed of innovation, and companies are continually improving their offerings to address the challenges of adopting the technology while enhancing the benefits. While 3DCP has been largely confined to small residential projects, for example, more commercial projects are emerging, as regulators become more familiar and comfortable with the approach and equipment makers develop larger-scale printers.

Being a first mover on 3DCP carries risks—but first movers have the opportunity to become leaders in a space if they can hold out long enough for it to develop around them. Being among the first to embrace this approach in a locale or for a certain type of structure could translate into a competitive advantage as adoption of 3DCP grows.