Concrete opens up new opportunities
Cement was rediscovered in 1824. Demand grew as plans were made to expand the railway network. Because of abundant limestone reserves, numerous cement plants were established at the end of the 19th century.
The invention of reinforced concrete paved the way for bold designs and modern architecture starting in 1890. Iron reinforcements within the concrete made the material stronger, and this reinforced concrete came to be used more often not only in bridges, but also in factories, silos, and warehouses.
But before concrete could declare victory, perimeter blocks began to be built in the cities at the turn of the century. These were four- to six-story tenement buildings, constructed around a courtyard and with entrances facing the street. There large working-class families lived in cramped, often precarious conditions.
In the 1920s, construction started to be seen in new ways. As cities expanded, there was a new emphasis on freestanding structures, coupled with innovative elements such as green spaces and parks. There was a growing awareness of the value of historical buildings and the need to preserve them. Today, culturally significant structures are regularly maintained and renovated.
In the 1930s, the spectacular Bel-Air Tower in Lausanne demonstrated what can be created using concrete, in addition to products of civil engineering such as bridges and dams. Built using neoclassical concrete elements, and 68 meters in height, it is considered Switzerland's first skyscraper.
During World War II, many building materials were in short supply. This caused a housing shortage throughout Switzerland, which, thanks to immigration, persisted until the mid-1970s. To address this challenge, generous funding was provided for housing construction, and this played a significant role in the country's economic recovery.
Concrete ultimately established itself as Switzerland's main building material in the 1960s. Machines continued to make building easier; houses were being erected more and more rapidly. Building plans were now being drawn up on computers and could be easily modified. It was not until the real estate crisis of the 1990s that construction slowed, bringing the building boom to an end.
The topics of protecting the landscape and spatial planning emerged as important issues. This led to an emphasis on greater density – particularly in crowded regions, where building land is scarce.
Sustainability and a circular economy
Since the beginning of the 21st century, the big topic in construction has been sustainability. Simultaneously, we are seeing a return to traditional building materials; clay and wood, for example, are experiencing a revival. In the city of Zug, planning has been underway since 2019 to build an 80-meter high-rise building out of wood.
Dwindling resources are forcing the construction industry to recycle materials. But the future belongs to a circular economy, based on the principle of reusing prefabricated, standardized components. These elements can later be disassembled and reused, with no need for additional processing – making it possible to close the materials and product loop. Steel and wood are particularly well suited for this purpose, but precast concrete components work well, too. In the construction industry, the idea of a circular economy is still in its infancy.
At present, the main focus is on optimizing existing synthetic building materials and developing new ones, such as highly durable, yet lightweight floor elements. At the same time, digital tools – such as BIM (Building Information Modeling) – are revolutionizing construction planning. These tools facilitate planning, maintenance, operations, and renovation, as well as monitoring the entire life cycle of real estate.
The house of tomorrow: Digitally printed and environmentally friendly
The cutting-edge, digitally fabricated DFAB HOUSE in Dübendorf was built using a combination of traditional construction methods and innovative digital tools. Digital technologies made it possible to construct this three-story building more sustainably and efficiently than would have been possible by relying on traditional methods.
It is the world's first inhabited building that was largely digitally planned and built using robots and 3D printers. The entire formwork for the 80-square-meter ceiling was produced using a 3D printer. In this smart house, kitchen appliances and the heating system are voice-activated. Resources are also conserved in the building's maintenance.
This futuristic house is part of the NEST research and innovation building, which is operated by the Swiss Federal Laboratories for Materials Testing and Research (EMPA) and the Swiss Federal Institute for Environmental Science and Technology (EAWAG). It was designed and built by the National Center of Competence in Research (NCCR) Digital Fabrication at the Swiss Federal Institute of Technology Zurich, in cooperation with numerous business partners. It remains to be seen whether, when, and in what form this building method will gain widespread acceptance in the construction industry.