At CRH, we identify and pilot the most promising and scalable technologies that will meet the diverse needs of our customers, and our ability to replicate and scale such innovation between geographies provides us with new opportunities for growth.
To this end, our materials businesses on both sides of the Atlantic have been experimenting with 3D concrete printing (3DCP), a revolutionary new construction method by which buildings are ‘printed’ from a plan, one layer of concrete at a time.
Conventional concrete construction relies on formwork and manual labor. 3DCP on the other hand does not require traditional formwork and is largely automated. A gantry crane system or a robotic arm essentially moves around on rails pouring or ‘printing’ continuous thin layers of concrete on top of one another], guided by computer programs that translate three-dimensional digital designs into a real structure. This “printing” uses a specially engineered mortar which is a fine-grained concrete material, with a specific consistency to feed the printing arm, and yet which holds up to the strength and durability required. The special mortar uses less water than conventional concrete mixes, which in turn reduces the drying and curing time. What’s more, this type of mortar and technology gives architects freedom of design, to build using complex shapes that simply aren’t possible with traditional concrete and construction techniques.
This innovative technique speeds up the construction process dramatically (printing is three times faster than traditional construction) while saving energy and eliminating concrete waste, and it allows the industry to build in places that may be lacking in quality manpower.
3DCP has the potential to play a critical role in modern construction, providing faster, more cost-effective, and sustainable ways to build for a growing population. Although in its infancy, it has already proven its potential for constructing at speed and could be a viable solution for emergency housing and infrastructure, as has been demonstrated by CEMARK, A CRH Company in the Ukraine.
CEMARK teamed up with the TEAM4UA foundation to construct Ukraine’s first school using 3DCP. CEMARK donated 40 tonnes of cement to help construct the walls of the new building which, thanks to 3D printing technology, were completed in a matter of weeks, rather than months. This demonstrates the application of 3DCP technology to construct in regions where vital infrastructure is required to be built or re-built at pace.
In Ireland, where a fast-growing population is causing an escalating housing shortage, Roadstone, A CRH Company, provided readymixed concrete for a 3DCP housing development - a European first. Supported by CRH’s Innovation Fund, Roadstone partnered with Irish 3D Construction Printing provider HTL tech, and the local authority, to pilot the construction of three houses. By leveraging 3DCP technology, the structures were 3D printed in just 12 days, and construction timelines were reduced by 35% compared to conventional methods. At its industry-leading R&D laboratory, Roadstone’s technical teams worked closely with HTL tech to develop the bespoke, low-carbon readymixed concrete, which was thoroughly tested to ensure full compliance with building regulations and material standards. The award-winning project received the 'Standards Innovation Award' from the National Standards Authority of Ireland (NSAI).
On the other side of the Atlantic, CRH’s Innovation Fund has also supported Oldcastle APG, in the development of an industry leading mortar, specially formulated for the precision of 3D printing. The company’s 3D Printing Mortar Mix was used to create three new concrete homes in Texas in 2024, each printed in just a few weeks. The first 1,200 sq. ft. home took approximately six weeks to print, with subsequent 1,500 sq. ft. homes completed in 3 to 3.5 weeks, following continuous optimization of machine setup, layer time and printing speed, all of which require tweaking based on site conditions, weather and more.
CRH is also exploring the possibilities of the application of 3DCP in infrastructure. Tarmac, A CRH Company in the UK, brought structured 3DCP to the country for the first time in 2023. Collaborating with Finnish technology company Hyperion Robotics, Tarmac created four bespoke drawpits for the water industry. Typically, drawpits are heavy, box-shaped structures placed underground for the containment of electrical cabling. At a sewage treatment plant in the north of England, the 3D-printed design, coupled with Tarmac’s lower-carbon cement, resulted in a 40% reduction in embodied carbon when compared to a conventional, in-situ drawpit.
This is just the beginning of 3DCP. As such, its scalability is still under exploration. However, the reduction in waste material, the faster construction time, and its ability to produce unique designs that are not possible with traditional concrete materials means 3D concrete printing is showing great promise for the future of construction. At CRH, we are excited to play our part in this this developing space.
