House from the 3D printer

The fact that the industry uses 3D printers for the production of prototypes has long been the norm. The construction industry has also recognized the technological potential for around eight years and has developed a series of innovative concepts that allow printed houses to be built, sometimes within just a few hours.

Architects and builders abroad have already turned a number of spectacular visions into reality. Here in Germany, too, the first house "sprang" from the printer in 2021. A good reason for us to take a closer look at this topic for you.

Houses in 3D printing: the key facts about the principle

We would like to make it clear right at the start: You cannot, of course, print entire houses "with all the trimmings". Windows, doors, heating, electrics, ceilings, roof, floor slabs - all of this has to be added. Only the walls can be printed.

The building material used:

Concrete - sometimes also in the finer-grained variant cement mortar - has so far been the material used for almost all 3D-printed houses. Although the first model houses have been built using more ecological materials such as vegetable oil, the advantages of concrete, including its reliable fire and noise protection, have clearly predominated in use so far.

How printing works:

The actual printing process for the walls is quickly explained. A computer controls the printing nozzles from which the fine lines of concrete emerge. The individual layers of concrete gradually pile up to form walls. As high as it was conceived and planned - also on the computer. The printing nozzles usually rotate around a single axis so that the lines can only run in a circle.

On shape and printing time:

The "typical" 3D house therefore also has a mostly circular base. If you want more "common" base shapes, you have to use two-axis variants, which are more complex and time-consuming to use. But even then, rounded and curved corners are typical, as are the walls, where the lines of the printed concrete are clearly visible from the outside. This characteristic "layered façade" is practically the aesthetic hallmark of printed buildings. However, the rule of thumb for the duration of the "build" is that the 3D printer takes around five minutes to print one square meter.

This is what is possible when 3D printing concrete houses:

• plastered or painted facades
• wood cladding
• basement buildings
• buildings with several storeys

A visit to a 3D printed house construction site is often reminiscent of prefabricated house construction. Prefabricated elements are delivered and assembled so that everything can often be ready in just a few hours.

A quick overview: Project examples for 3D-printed houses

We have selected three properties for you to illustrate the advancing technological developments and possibilities. These include the first 3D-printed house to be built in Germany.

1. 2014: Pioneering work in the Netherlands. One of the first objects, the small art pavilion "3D Print Canal House", was created in Amsterdam in 2014. Only 8m² in size, it was printed from a thin - completely recyclable - plastic thread. The entire construction time was estimated at three years at the time. Here you can find pictures of the pioneering project, which even attracted the interest of the US government at the time.

(If you are interested in other minimalist living concepts: In this article, we have summarized relevant information on the topic of "Tiny House".)

• 2018 & 2020: Sustainability pilot projects. Since 2018, the "Gaia" pilot project, a house printed from a CO2-neutral material mix of plant fibers, raw soil and lime, has been open to visitors in Italy. A similar project called "TERA" has been on show in the state of New York since 2020 - here, the material used is a fully recyclable bio-plastic, originally developed for NASA.

2. 2019: Administration building in Dubai. 9.5 meters high, 640 m² of interior space, erected in just two weeks - with the world's largest 3D printed house (as of 2020), the emirate has underpinned its claim to leadership in this area in the truest sense of the word. By 2030, a quarter of all new buildings on site are to be created using 3D printers. Find out more about this printing superlative here.
   
   
3. 2021: The first 3D printing house in Germany. In Beckum, North Rhine-Westphalia, a two-storey detached house with 160 m² of living space was built in July 2021, this time after just under 100 hours of printing. The printer was fixed in a metal frame and applied the concrete in layers, each 2 cm thick. Here you can find more information about this construction project, which is still unique in this country and is seen by the initiators as a possible model for accelerating the creation of new local housing.

Advantages and disadvantages of a 3D-printed house

It is important to realize that this technology is still in its infancy in this country. The pioneering house in North Rhine-Westphalia is also initially intended to serve as a model and illustrative object and will not be used as an actual residential model until 2023. If you would like to find out more about the advantages and disadvantages of buying a house from a 3D printer today, you will find a compact summary below.

The advantages of 3D printed houses:

• Fast printing. Depending on the size of the object, printing the walls usually only takes a few hours. After a maximum of four to five days, for example, the foundation walls for an approx. 160 m² detached house can be ready.
  
  
• Environmentally friendly mix of raw materials. Some of the load-bearing structures can be printed from raw soil, lime, straw and plant fibers - a completely biodegradable combination of raw materials.
  
  
• Efficient use of materials. Only as much is printed as is needed.
  
  
• A pleasant living environment. Fully compostable raw materials as building materials usually meet the highest criteria for healthy living.
  
• Sustainable future concepts. As we have seen, companies have already developed building materials for 3D buildings made from purely natural raw materials. This gives us hope that 3D houses will also increasingly stand for better environmental compatibility and a better CO2 balance in housing.
  
  
• Innovative pioneer living. With the striking circular architecture of 3D printed houses, interested parties can discover a previously rare form of living for themselves.
  
  

The disadvantages of 3D printed houses:

• Few providers. As an interested party, you can hardly make any comparisons because offers for private customers are still rare on the market.
  
  
• More expensive than conventional construction methods. For a house with a comparable floor area and number of storeys, you still have to accept additional costs of around 10 to 15% if you want a variant from the 3D printer. Although prototypes are available from as little as 10,000 euros, they usually do not comply with the applicable building regulations.
  
  
• Lack of experience. So far, only a few people can be asked how comfortable it is to live in a 3D printed house. There is hardly any long-term experience due to the novelty of the technology. This creates uncertainties, especially with regard to living comfort, insulation and energy supply.

Conclusion: The first 3D-printed house will be built in Germany in 2021, proving that this type of construction can be used to comply with current building regulations. However, it remains to be seen whether this technology will prevail in the long term and, above all, whether the disadvantages in terms of costs and sustainability can be turned into advantages.