by Justin Kinsella – Director of Harcourt Architects and Harcourt Technologies Ltd


How did you get into 3D Construction Printing (3DCP)?
HTL.tech is a team of architects, engineers and materials scientists interested in modern construction methods. Working as architects, we were first introduced to 3DCP when tasked with analyzing construction methods suitable for delivering affordable and sustainable social housing projects in the North UK. After a chance encounter with someone in the 3D additive manufacturing industry and we saw the potential and began to research the area immediately.
We started looking at the different equipment available and studied precedent projects underway in the US and Germany. It was apparent that 3DCP could address many of the issues facing construction, such as high cost, labour shortages, and waste generation. If 3D printing could solve these problems and also achieve regulatory compliance in Germany and elsewhere, we thought it should be possible to replicate and employ the technology here.
We first came across COBOD International in early 2021 and subsequently travelled to their headquarters in Copenhagen for an introductory meeting where we got to see the equipment in action. We found them and their team to be very impressive and progressive. Soon after, we established a working partnership with COBOD for the distribution of the technology in the Irish and UK markets.
How does 3D Construction Printing work?

The printer works similarly to a cake icer – the print-head (which operates from a gantry system) extrudes one layer of concrete at a time around a pre-determined pathway. As long as concrete keeps flowing to the print head, the printer can apply concrete, layer by layer, until the building superstructure is complete.
The printer is a construction tool with multiple potential applications. It can be used to build homes or apartments, but many other uses exist for infrastructure and aesthetic applications. Notably, GE Renewables, an investor with COBOD, sees real potential in using the technology to build wind turbine bases.
Is 3DCP Sustainable?
Our research has shown that 3DCP can reduce waste by up to 70%, attributed to reduced formwork requirements, targeted deposition, and improved tolerances. The EU’s forthcoming legislation for the construction industry seeks to minimise construction emissions by 80% through greater material efficiency, so 3DCP could have an impact there. Other factors will be the increased use of recycled aggregates, printable geopolymers and low-carbon concrete, utilising innovative binders from waste stream constituents.
That only tells the materials side of the story though. A major factor is the accuracy and consistency of the printed objects. This means that the other components involved in the construction process can be reliably specified and ordered in advance. These can then be smoothly incorporated into the printed structure, delivering consistent air-tightness within the building envelope at unprecedented rates. Since we can now bring the factory to the building site, CO2 from transport is also significantly reduced as the material used in the project can be sourced locally.
Taken altogether, 3DCP contains building blocks required to decarbonise the built environment. If we could concurrently harness these opportunities, we could be looking at a scenario in a few years where 3DCP could become one of the most sustainable construction methods.
So what’s next for the 3DCP industry according to Harcourt Technologies?

Another major problem facing the construction industry is the shortage of skilled labour, and 3DCP can help to address that. Currently, educating the construction industry and prospective industry entrants about the process and benefits of 3DCP is crucial. There is great potential for universities and technical colleges to get ahead of the curve and a partnership between academia and industry is essential to promote the absorption of the technology.
Innovation is what got us to this point, but there is still so much more potential to uncork in the area of 3DCP, from both a machinery and a materials point of view. Disrupting any traditional sector is complex, and we realise that the better we can showcase these benefits, the more convinced the construction sector will become that 3DCP represents a considerable opportunity for innovation and collaboration to streamline the building process and address the sustainability issues we face as an industry.
About HTL
Harcourt Technologies Limited, Harcourt Architects’ sister company, is the sole distributor of COBOD 3D construction printers and equipment within the territories of the Republic of Ireland, Northern Ireland and the United Kingdom. They supply a range of machines for use in the printing of both mortar and concrete structures. Their team draws from over 20 years of experience in architecture, development and traditional 3D additive manufacturing.