Article
From building materials to construction techniques, construction has changed dramatically over the past 2,000 years. The construction industry is focusing on such topics as a circular economy and recycling, while new technologies and applications are revolutionizing real estate planning and construction. At the same time, the industry is rediscovering traditional building materials.
February 7, 2022
Even the ancient Romans were familiar with concrete. With the fall of the Roman Empire, however, it was forgotten. The concrete was of exceptionally high quality, as demonstrated by the Pantheon in Rome, which was built in the year 120 A.D. Its massive concrete dome, measuring 43 meters in diameter, has survived to the present day.
In Switzerland, beginning in the Middle Ages, major construction projects undertaken by the aristocracy, the church, and the cities relied almost exclusively on stone. Most building materials were from the local area, but this was not true of the architects and builders themselves. Many of them came from far away – from France, Italy, or Austria, for example – bringing architectural influences with them to Switzerland.
During Switzerland's preindustrial period, wood was the most important building material. In terms of quality, there is no comparison between the buildings of that era and modern structures. The wooden buildings of that time were often severely damaged by fire or floods, as well as by military conflicts. Regular repairs were required, turning villages and towns into permanent construction sites.
As industrialization began at the end of the 18th century, there were shortages of wood because it was needed as fuel for operating steam engines. Inevitably, the use of stone in construction became more frequent, including in rural areas.
As industrialization continued, there was a need for new structures such as factory buildings, bridges, and train tunnels. The first factories were built in the early 19th century, and it became increasingly common in the cities to separate living and working areas. People lived in houses and went to work in factories. In rural regions, living and working under one roof continued for a longer period of time, and in some cases that arrangement persists even today, for example on farms.
During that era, most houses were built by hand. Construction work was poorly paid and often dangerous, owing to a lack of safety regulations. Accidents were an everyday occurrence. In many cases, this was because of the poor quality of building plans; architectural training had not yet been standardized – something that did not change until the middle of the 19th century.
With the founding of the Swiss Federal Institute of Technology (ETH) in 1855, comprehensive training for architects was introduced, leading to a steady improvement in construction quality. This was urgently needed, because Switzerland experienced strong population growth beginning in 1850. As industry boomed in the 19th century, many workers flocked to the up-and-coming cities, creating a shortage of affordable housing.
Some relief was provided by the first workers' settlements, which were built between 1860 and 1875 in Geneva, Lausanne, Bern, Zurich, La Chaux-de-Fonds, Le Locle, and Winterthur. The builders of the settlements introduced the first standards requiring ample sunlight and ventilation in the housing units, and they created green spaces where residents could grow their own food. Switzerland's cantons passed the first laws governing construction at the end of the 19th century, in some cases incorporating the standards that had been set for the workers' settlements.
City of Bern: Medieval city
Building material: Sandstone
Perimeter blocks in the city of Zurich (1900–1930)
Building material: Brick
Switzerland's first high-rise building:
Bel-Air Tower, Lausanne (1930s)
Building material: Concrete elements
Greencity: It's all about sustainability
In 2012, Greencity was certified as Switzerland's first "2,000-Watt Site."
DFAB HOUSE (illuminated building at right on the upper platform)
The DFAB HOUSE in Dübendorf is the world's first inhabited building that was planned and built using primarily digital tools.
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.
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 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.
