If only a few years ago 3D printing was viewed with a certain suspicion, recent news has shown that it is in fact a viable technology that is here to stay. On April 30, 2021, tenants of the first 3D printed concrete house in the Netherlands received their keys. The house in Eindhoven—the first of five within the 'Milestone Project'—fully complies with all the country's stringent construction requirements.
The single story building has 94 square meters of floor space, including a living room and two bedrooms. It replicates the shape of a large rock, which fits well with the natural site and demonstrates the freedom of form offered by 3D concrete printing. Thanks to extra thick insulation and a connection to the heating network, the house is highly comfortable and energy efficient, with an energy performance coefficient of 0.25.
The house consists of 24 printed concrete elements that were printed layer by layer at a factory in Eindhoven. The elements were then transported by truck to the construction site and placed on a foundation. The house was then equipped with a roof and window frames, with finishes applied afterward.
According to the team, it was especially challenging to print the building's inclined walls, but learning from the prototype helped them master the technique in the next 4 buildings planned. Concrete has been the most widely used building material in the world for decades and we are all by now familiar with it; we know how and where it should be used. Traditionally, we pour concrete into wooden or metallic formwork, and end up using much more than necessary for the construction. The more that is used, the worse the building's CO2 emissions and the worse its greenhouse effect. One of the great advantages of 3D printing is that the concrete printer has the ability to place concrete only where it is needed, without overloading the foundations and without wasting materials.
In principle, printed houses can be built much more quickly, with more flexibility and potential for custom designs. The ambition of the Milestone Project partners is for 3D concrete printing to become a sustainable construction method that contributes to solving the housing deficit. According to Theo Salet, Professor of Concrete Structures at Eindhoven University of Technology: “With this small building, a first major step has been taken today in the development of construction into a high-quality manufacturing industry. From design to implementation, digitalization leads to sustainable and affordable homes tailored to the wishes of the occupant.”
The five houses of the Milestone Project are being built one after the other so that each new round of construction can maximize learning opportunities from the previous ones. Soon, the project partners will start working on the design of the next building, which will have several floors and, therefore, require further development of the technique.
Pieter Knauff, Investment Director at Vesteda, adds that “3D concrete printing’s freedom of form creates an enormous new scope of possibilities in the design and experience of a home. At the same time, this new technique contributes to the required sustainability in the construction industry, the acceleration of building production and the control of construction costs, which is much needed in order to continue building affordable homes.”