3D concrete printing: the technology that promises to build a house in 48 hours and is already used in Argentina

These machines, which made the transition from laboratories to the home, evolved in such a way that in different countries they are already building homes, buildings, bridges, railway stations and commercial premises using enormous robotic arms that deposit layers of concrete following a digital plane. Now that trend has also begun to gain strength in the Argentina.

The technology is known as concrete 3D printing (3DCP) and seeks to modify one of the most traditional stages of construction. In Argentina it is still an incipient technology, but they already exist concrete projects and companies that are betting on it.

One of the local protagonists is Land locationthe entrepreneurship of the technological entrepreneur Mateo Salvattowhich brought a printer from the Danish company COBOD to the country. The machine has a scale that is difficult to imagine for someone used to a home printer: approximately 11 meters by 11 meters and 7 meters high.

The objective of this company is to bring to the world of construction some of the advantages that made additive manufacturing attractive: automation, precision, less waste, and the ability to produce geometries that would be more complex or expensive using traditional methods.

One of the most striking data points about this technology is its speed. In dialogue with ClarionSalvatto explained that the work program contemplates approximately 48 hours of printing for a home 120 square metersincluding walls and double wall configuration with air chamber.

However, he clarifies, this does not mean that a family can move into a house two days after starting printing. This period corresponds to the printing process of the part of the construction carried out by the machine. Then you have to complete the rest of the work, like any other undertaking.

“The first reaction people have is to tell you: ‘How are you going to build a house in 48 hours?‘. But this is really super, super fast. If you want to have a technical variable, the machine can practically reach two cubic meters per hour,” Salvatto said.

“If you do an 8-hour shift, it takes you six shifts. If you do two 8-hour shifts, you are taking just three days. “We are already arguing for hours when today we discuss for weeks or months,” he added.

Precisely, the main difference is that a task that traditionally requires a succession of workers, materials and processes can be automated through a digital file that determines where, when and how much material should be deposited.

3D printers are characterized by materializing any type of design through various materials. The most notable variants are FDM (plastic casting by nozzle), SLA/LCD (solidification of liquid resin with light) and SLS/DMLS (fusion of metal or plastic powders using lasers) that are present in laboratories or large industries.

Even the additive manufacturing also reached steel. One of the best known experiences is the pedestrian bridge created by the Dutch company MX3Dbuilt using technology wire arch printing (WAAM)which deposits successive layers of stainless steel.

In the case of those that use concretethe principle of operation is similar, although to a completely different scale. Instead of melting plastic, these machines mold a special concrete mixture using a head installed on a robotic arm or a huge automated gate.

It all starts with a three-dimensional model designed by architects and engineers. This file is processed by software that divides the project into hundreds or thousands of horizontal layers and generates the exact path that the robot must follow.

Meanwhile, a mixing plant It continuously prepares the mortar and sends it via a pump to the print head. Instead of plastic, special cement mixtures are used along with plasticizers, accelerators and other additives that modify its behavior during printing.

Then, begins the construction stage.

The main function of this machine is lift the so-called gray workthat is, a good part of the structure and the walls. Installations, openings, painting, coatings and finishes continue to require conventional methods and labor.

The nozzle deposits continuous strands of concrete following the path defined by the computer. Each new layer builds on the previous one. to form walls, internal divisions, stairs, benches, flower beds or even part of the integrated furniture.

According to Salvatto, the machine works with a precision of the order of millimeters, with an estimated deviation of around five millimeters in positioning.

Of course, the printing process It does not eliminate the possibility of errors. In fact, the main problems can appear in the design, in the preparation of the mixture or during operation. But digitalization allows reduce some of the detours usual for a work.

In conventional construction there are cuts, leftovers, material movements and other processes that can generate waste. In 3D printing, the machine deposits material only where the digital design indicates it should.

Salvatto estimates that the system could generate a saving close to 30% versus a traditional constructionalthough it clarifies that this is an estimate that depends on variables such as the terrain, location and characteristics of each project.

Part of this reduction in the budget of the work is related to time, logistics and less waste. Also with the possibility of reducing the equipment necessary to specifically execute the gray work.

That does not mean, however, that 3D printing will eliminate workers of construction.

“The other 70% of the work is traditional and requires the same traditional bricklayers. The guy who makes the openings, the painter, the plumber, that is, That’s going to be the same,” Mateo remarked.

“We do not believe and we do not expect that this is something that will considerably reduce labor. Obviously any automation always has an impact on labor, but it is neither the objective nor do we want it to be like that. Quite the opposite, we want this to generate better working conditions”, he claims.

The difference is in what tasks they perform. The printer can take care of a particularly physically demanding part, such as the repetitive movement and placement of materials to erect walls.

The homes built using this system have a double wall and air chamber, improving thermal and acoustic insulation compared to many traditional systems. Furthermore, the structural continuity offered by printing favors the anti-seismic behavior and allows the construction of curved geometries with practically no extra costs.

While a curved wall usually considerably increase the budget In a conventional work, for a printer it represents simply another computer-programmed path.

While the private sector advances with commercial and infrastructure projects, in Argentina there is also an initiative with a different objective. The National University of La Plata (UNLP)together with the Río Santiago Shipyard, developed a prototype of a concrete 3D printer designed specifically for the construction of social housing.

The Argentine team is approximately six meters wide and three meters high and can adapt its length according to the needs of the project.

The stated objective is print a 60 meter house squares in about 50 hours, including the internal divisions and the spaces provided for the openings.

The development also includes its own cement mixture, designed and tested by professionals and scholarship holders from the UNLP Faculty of Engineering. The formulation seeks to respond to both the printing needs and the structural requirements of a self-supporting home.

Unlike a system that depends exclusively on imported components, the project seeks to locally develop both the machine and part of the technology necessary to operate with it.

The initiative also incorporates work cooperatives for different stages of construction and facilities, with the idea of ​​combining automation and job creation.

In the case of Grondplek, the company began thinking about housing construction and aims to develop its first inhabited projects in Argentina towards the beginning of 2027. Meanwhile, the first machine incorporated into the country has already found an application in infrastructure and civil engineering through Techint Engineering and Construction.

The same machine that can print the walls of a home can be used for offices, infrastructure, modular stations, urban components or engineering projects.

Therefore, more than a 3D printer that simply “prints houses”, what is appearing is a new manufacturing tool applied to construction. And its greatest potential may not only be in building walls faster, but in solving a historic housing problemwhile changing the way the spaces where we live are designed, produced and built.