Monument conservation and restoration are undergoing technological change. Where craftsmanship used to be the main skill required, digital precision, automated processes and intelligent analysis systems are now increasingly at the heart of conservation work. The combination of traditional knowledge with modern technologies enables new ways of preserving cultural heritage – in a way that is gentle on materials, sustainable and efficient. This interdisciplinary approach is not only changing the approach, but also the training and professional profiles in the field of restoration.
Modern and digital technologies are increasingly being used in restoration and monument conservation.
Photo: Dr. Schorsch, CC BY-SA 3.0 via Wikimedia Commons
Digital surveying: 3D laser scanning as the basis for modern preservation
3D laser scanning is a key tool in contemporary monument conservation and restoration. This method allows historical buildings, statues or frescoes to be recorded with millimeter precision and completely contact-free. The resulting point clouds can be converted into digital models that serve as a working basis for architects, restorers and heritage authorities. Contactless documentation is a great advantage, especially for sensitive or endangered objects. The process was used in the course of the Notre Dame restoration in Paris, for example, where earlier laser scans were used to reconstruct the vault exactly. 3D scans also provide valuable services in war zones and disaster areas, for example in the restoration of destroyed sites in Syria. Increasingly, such scans are also being used for virtual exhibitions and digital museum spaces to make cultural assets accessible worldwide.
Digital buildings: BIM in monument preservation
While Building Information Modeling (BIM) has long been at home in new construction, it has now also arrived in heritage conservation, where it is being further developed as “Heritage BIM” or HBIM. The digital twin of a historically valuable building contains not only geometric data, but also information on materials, damage, restoration and usage history. This creates comprehensive digital archive systems from which maintenance, renovation and use can be planned efficiently and comprehensibly. One example of this is the digitized building management of Bellevue Palace in Berlin. HBIM not only enables better communication between all parties involved, but also long-term conservation based on valid digital data – a decisive step towards sustainable monument protection. International collaborations also benefit from HBIM, as complex restoration processes can be coordinated across locations.
Reconstruction at the touch of a button: 3D printing in restoration
3D printing offers one possibility for supplementing lost building fabric. In combination with laser scans or digital reconstruction data, destroyed or missing elements such as sculptures, decorative profiles or tracery components can be reproduced with high precision – often using reversible materials that do not damage the original work. Monument workshops such as the Dombauhütte Cologne are now testing 3D printing for the production of temporary or test components. The focus is always on ensuring that such interventions harmonize both technically and aesthetically with the existing structure. Universities, such as the Vienna University of Technology, are also intensively researching and working on 3D replicas of historical elements. In addition, the first approaches are being made in which entire façade elements can be produced on site with the help of 3D printer-based robots.
Intelligent analysis: Artificial intelligence and digital simulations
Modern simulation methods in heritage conservation and restoration range from thermal analyses and climate simulations to structural calculations of historic building components. In combination with artificial intelligence in particular, this opens up new potential for condition diagnosis and risk prediction. For example, AI systems can learn to automatically recognize crack patterns on façades and predict their development. Digital tools such as WUFI or Delphin make it possible to visualize how moisture or salt migrates in historic masonry and help to plan targeted renovation strategies. Digital simulation also offers the opportunity to develop solutions for the energy-efficient refurbishment of listed buildings without endangering the historic substance, especially in combination with sensor networks, creating intelligent monitoring systems that record and interpret changes in real time.
Gentle cleaning: Laser beams instead of brushes
Laser cleaning is being used more and more frequently in restoration – especially when cleaning sensitive materials such as sandstone, plaster, wood or metal. Targeted laser pulses are used to remove impurities or deposits without damaging the original material surface. The great advantage of this method is that it is contact-free, leaves no residue and can be adjusted in such a way that even intricate details are preserved. The Naumburg Cathedral, for example, was freed from decades-old layers of dirt using laser technology – with visible success and without any loss of material. The combination with imaging methods such as hyperspectral analysis allows the cleaning process to be controlled with pinpoint accuracy.
New perspectives: robotics and drones in use
Drones and robotic systems are now part of everyday life in modern heritage analysis. They take high-resolution images, record aerial photographs, document areas that are difficult to access such as roof trusses or church towers and thus provide the basis for restoration decisions. Mini robots with 3D cameras or infrared scanners also record interiors, vaults or obstructed areas. In Zurich, a drone with a gripper arm has been developed that can take samples of façade materials – a prime example of how robotics and cultural heritage protection can work together. This opens up a new, secure field of documentation, especially for threatened or acutely damaged buildings. In combination with AI-supported image recognition, these systems can identify and document potential damage at an early stage.
Materials research as a silent revolution: conservation with nanotechnology
Not all advances in heritage conservation are immediately visible: research and technology are also leading to far-reaching innovations in the materials and chemicals used. Restoration laboratories are now developing specific nanoparticle hardeners for weathered sandstone or encapsulated adhesives for fragile wall paintings. The aim of such developments is always the reversibility of the intervention, i.e. the possibility of reversing the measure later without leaving any residue. A research project such as “DigiGlue” is explicitly dedicated to the development of digitally controllable bonding processes in order to secure sensitive murals effectively and safely. New materials are also being developed in microbiology that inhibit biological growth on wall and roof surfaces – without aggressive chemicals or environmental pollution. In this way, biotechnologically optimized materials not only contribute to protection, but also to the sustainability of the measures.
Opportunities and challenges
Technological development offers enormous opportunities for heritage conservation – provided that the resources used are applied sensitively and responsibly. Digital tools, high-tech devices and artificial intelligence will never replace the craftsmanship and experience of conservators. But they expand the toolbox of heritage conservation enormously and enable new conservation strategies, planning models and forms of documentation. Especially in times of scarce resources and increasing pressure due to climate change, these innovations are crucial for making historical heritage fit for the future. In this context, the exchange between science, craftsmanship and authorities is becoming increasingly important in order to exploit the potential of new technologies in harmony with monument conservation principles.