The development of new construction materials such as steel and reinforced concrete, along with increasingly reliable engineering models, opened up unprecedented possibilities for designers during the High Modern period (approximately 1880–1970). This enabled a pursuit of ever greater spans and heights while simultaneously minimizing material use. This exploration of structural limits—pushing to the edge of what was physically possible—was accompanied by a growing restriction through codified limits of what was permissible, as regulatory frameworks steadily expanded.

The recently published volume “Building at the Limit” brings together contributions from the Think Tank of the same name within SPP 2255. These explore the practices, mindsets, and attitudes of engineers operating within the tension between these opposing facets of high modern construction. This novel approach to recent architectural history is complemented by insights into the continuities and ruptures of high modern efficiency thinking in today’s construction industry.

These explorations are further enriched, on the one hand, by the presentation of key milestones in high modern structural design—paradigmatic buildings as well as lesser-known projects that vividly illustrate specific aspects of building at the limit. On the other hand, interviews with contemporary witnesses—the structural engineer Rolf Heider and the construction historian Rainer Graefe—offer in-depth perspectives on professional practice as well as on the early stages of scholarly research into high modern construction at its limits.

Published by Birkhäuser, this volume is the first in the series “Structural Cultural Heritage – Texts on the Built Heritage of the High Modern Era.” The series presents the outcomes of the individual Think Tanks of SPP 2255, each supplemented by selected milestones and interviews with contemporary witnesses corresponding to the respective annual themes.

The 5th Denkwerkstatt 2026 in Munich is dedicated to the theme “Preserving the Future – Perspectives for Structural Cultural Heritage.”

The fifth and final Denkwerkstatt of the DFG Priority Program 2255 “Structural Cultural Heritage” (SPP 2255) is more than a traditional academic conference. In line with the 2026 annual theme, “Preserving the Future – Perspectives for Structural Cultural Heritage,” it was aimed not only at researchers but also at practicing architects and engineers. Recognized as a continuing education event by professional chambers, it brought together reports from current research with knowledge and experience from construction practice in existing buildings—serving as a forum for innovation, exchange, and new perspectives.

At its core were ten presentations by national and international experts addressing current fields of innovation and broader questions surrounding shifts in values within the construction sector. The first thematic block focused on new digital and analog methods for assessment, planning, and preservation. Among the topics presented were AI-supported techniques for damage documentation, heritage management with AI assistants, digital twins, and BIM applications for the renovation of complex infrastructure. These forward-looking topics were complemented by newly developed methods for analyzing historic concrete surfaces, a deeper understanding of deterioration processes, and strategies derived from this knowledge for repair and strengthening. In this way, the Denkwerkstatt bridged technological innovation and material-focused expertise.

A second focus addressed the often challenging tension between engineering, heritage conservation, and construction practice. Different professional cultures, languages, and evaluation standards meet here—creating both potential for conflict and significant opportunities. Using concrete examples, such as the ongoing renovation of the Munich Olympic roof and the institutionalized heritage conservation practices of the Swiss Federal Railways, the speakers demonstrated how sustainable models of cooperation can emerge. The goal is to establish a new, integrative culture of building preservation that brings together technical expertise, historical responsibility, and societal values.

A third thematic block turned to education and the transfer of knowledge into practice. Given that the majority of construction work now takes place in existing structures, international contributions from Portugal, Belgium, and Switzerland discussed new academic and continuing education models. These focused on engineering for historic structures, closer integration between universities and practice, and innovative teaching formats such as virtual reality. This made it clear that the necessary paradigm shift—from new construction to adaptation and transformation—begins in education.

The Denkwerkstatt was framed by a keynote from Prof. Dr. Armin Nassehi (LMU Munich). The renowned sociologist addressed how real change can be achieved—not through moral appeals or technology alone, but through the deliberate shaping of social structures.

The program is rounded out by two excursions that deepen the dialogue between theory and built reality (with limited participation). The Denkwerkstatt thus positions itself as an open space for communication: for exchange on equal footing, for new perspectives, and for sustainable strategies in dealing with our built heritage.

The 6th Common Ground 2026 in Dresden is dedicated to science communication in the history of construction technology.

With the conclusion of SPP 2255 in sight, the central question is: How can we effectively communicate our research results to the public and generate interest in our topics? High modernist buildings are often overlooked by the general public or perceived as unattractive—a key challenge in communicating their technical and cultural significance.
Three exciting specialist presentations on the topics of “Storytelling & Valorization,” “Gamification and Digital Formats,” and “Interaction with Civil Society” provide practical ideas and creative strategies for revealing the “hidden values” of buildings that are significant in the history of construction technology. In working groups, participants will develop concrete communication concepts for their projects – supported by experts and in interdisciplinary exchange between architectural engineering history, monument preservation, and civil engineering.

The newly published volume „Stahl auf neuen Wegen“ brings together contributions from the conference of the same name, „Stahl auf neuen Wegen. Historische Innovationsdiskurse, bautechnische Praktiken und denkmalpflegerische Herausforderungen der Hochmoderne“, which was held on April 20–21, 2023, in Stuttgart in cooperation with SPP 2255. Published in the renowned series „Kultur und Technik“ by the International Center for Cultural and Technological Studies at the University of Stuttgart, the volume—edited by Thomas Schuetz (subproject Erfolgreich Scheitern [G2])—opens up new perspectives on a building material that, like hardly any other, shaped high modernism.

Steel as a material uniquely represents the departure into modernity. Whether spectacular bridges, iconic television towers, or little-known prefabricated houses, steel revolutionized construction and continues to shape our built environment to this day. Contributions from the history of art, architecture, and technology, developed within the framework of SPP 2255, offer new approaches to understanding how steel not only opened up new forms and possibilities but also became a reflection of political, social, and cultural developments. Moving beyond common myths of progress, the volume thus provides surprising perspectives on the structural heritage of high modernism—and tells new stories of a material that has transformed our society.

On January 20, 2026, the public award ceremony for this year’s ICOMOS student competition “1960+ / Construction” took place at Bauhaus University Weimar. The competition, organized by the German National Committee of ICOMOS, the Wüstenrot Foundation, Bauhaus University Weimar, and the Working Group on Theory and Teaching of Heritage Conservation, was initiated with the support and cooperation of SPP 2255.

Complementing the research on the structural heritage of high modernism in Germany (1880–1970) conducted within the subprojects of SPP 2255, the student competition focused on the constructive heritage of the late 20th century. Students of civil engineering, architecture, interior design, urban planning, art history, restoration, archaeology, or other heritage-relevant disciplines were invited to investigate either the heritage qualities and values of a self-chosen example or to develop strategies for its (continued) use, renovation, or mediation. The nearly 50 contributions, some produced by pairs of students, presented a surprising panorama of projects, including innovative solution proposals. A selection of the contributions, each presented on an A1 poster, was exhibited in advance of the award ceremony at Bauhaus University Weimar and can be viewed online at ICOMOS.

At the beginning of the award ceremony, organized by Kirsten Angermann (subproject Construction-Inherent Values [H2]) in the historic Bauhaus building in Weimar, Roland May, the scientific curator of SPP 2255, gave a lecture on “Constructed Cultural Heritage: Blind Spots in Architectural History and Heritage Conservation.” In his talk, he explained the complex relationship between architecture and construction in modernity and highlighted the ongoing insufficient recognition of the contributions of the primarily civil-engineering-trained constructors in architectural reception.

Following this, the authors of the prize-winning entries, which were awarded cash prizes totaling €5,000, presented their work. Each presentation was followed by detailed appreciation and discussion by members of the jury: Tino Mager, President of ICOMOS Germany; Daniela Spiegel, from the International Heritage Center and head of subproject DENKRAUM (D1); Philip Kurz, Managing Director of the Wüstenrot Foundation; Ines M. Jauck, President of the Chamber of Architects of Thüringen; and Roland May.

SPP 2255 congratulates all the award winners!

The series of Footbridge Conferences has established itself as an international forum for the latest developments in pedestrian bridge construction. Engineers and architects from around the world come together to exchange ideas in this subfield of construction, which is particularly open to innovative approaches. For this year’s conference in Chur, Switzerland, Werner Lorenz was invited to deliver a keynote. Under the title “Shifting values – repair and reuse,” he addressed the background and guiding principles of an approach that is also central to SPP 2255: preserving and continuing existing structures rather than demolishing and rebuilding.

After Berlin (2019) and Madrid (2022), the Swiss city of Chur was the host of Footbridge_2025. The choice of location was justified, among other reasons, by the high density of impressive historical and modern bridges in the surrounding canton of Graubünden, but above all by the fact that one of the world’s most prominent bridge builders, Jürg Conzett, is based here—teaching and, most importantly, building. Well over 200 participants attended the lectures and presentations from September 3 to 5, which covered the full range of different aspects of pedestrian bridge construction. The conference concluded on September 6 with a excellently organized excursion to outstanding bridges in the area, some of which have gone down as milestones in the history of structural engineering.

In his keynote, Werner Lorenz drew attention to a topic that has long been taken for granted in SPP 2255 but remains rather marginal in pedestrian bridge construction: preserving and continuing existing (bridge) structures as an alternative to their premature demolition and replacement. Referring to this year’s Venice Architecture Biennale, he began by noting that such concepts now enjoy top priority in construction in general, yet in bridge building they still play only a minor role. From a historical perspective, this is particularly puzzling: repair and maintenance were widespread practices for millennia, and it was only with late modernism that the idea of the fundamental superiority of new construction (compared to the development of existing structures) gained prominence.

In the second part of the keynote, Werner Lorenz outlined several central guidelines for a fundamentally new approach to 21st-century construction, one increasingly committed to preserving the existing built environment—a profound shift that has become unavoidable in practice under the “sustainability turn,” while also opening up new ways to incorporate cultural heritage considerations. The text of the keynote is available for download.

The demolition of the Ohetal Bridge would mean the loss of an exceptionally valuable testament to 19th-century engineering. Completed in 1877 as an impressively delicate lattice truss structure, it appears to be largely preserved in its original state to this day. The remarkably high authenticity of the structure is further enhanced by its significant importance in construction engineering history: with Heinrich Gerber—head of the South German Bridge Construction Company responsible for the iron superstructure—one of the leading German bridge engineers of his time was directly involved in the project.

The clear, unornamented truss design exemplifies an engineering aesthetic that, already in the late 19th century, anticipated key characteristics of later architectural modernism. Even contemporary accounts praised the successful design of the Ohetal Bridge as a structure of “overwhelming impression.” Yet the cultural significance of such engineering structures goes far beyond their successful design. Just as a Romanesque monastery, a late medieval timber-framed street, or a Baroque garden are undisputed cultural heritage sites that today communicate the social conditions, ways of thinking, values, and capabilities of their time, so too do the bridges of the late 19th century—materialized in cast iron and steel—stand as testimonies to the production conditions, engineering practices, design ideals, and above all, the unbroken belief in progress that characterized the era of high industrialization.

Despite this, even the very few surviving railway bridges of that time are threatened with demolition nationwide. For a long time, the arguments cited for their removal were considered compelling, and in particular, material fatigue in steel bridges is a serious concern. However, current research approaches and findings allow for more nuanced assessments of actual load-bearing and fatigue capacity, as well as novel options for targeted, localized reinforcement while preserving the structure as a whole. Initial successful examples strikingly demonstrate the potential of such approaches. Ultimately, they can not only help preserve the “construction heritage,” but also offer an ecologically far more sustainable alternative to outdated new-build thinking: namely, repair and adaptive reuse.

Even though we do not know the specific technical or functional reasons that may make the preservation of the Ohetal Bridge appear impossible, we urgently appeal to the responsible authorities and decision-makers to critically scrutinize these arguments with great care, and to seriously and proactively consider possible—perhaps even unconventional—alternatives for preservation. Preserving outstanding examples of historic infrastructure is not an exercise in nostalgia – it is a responsible contribution to a culture of construction that is both mindful of memory and committed to sustainability.

Univ. Prof. Dr.-Ing. Werner Lorenz and Dr.-Ing. Roland May – on behalf of SPP 2255.

Ohetalbrücke, Montageplan für Öffnung I, Stand September/Oktober 1876 (Deutsches Museum, NL 044/0526, Bl. 8, CC BY-SA 4.0, https://creativecommons.org/licenses/by-sa/4.0)

A visit to the Hohenlohe Open-Air Museum in Schwäbisch Hall-Wackershofen.

Together with the FH Augsburg and LMU Munich, the Department of the History of Technology at the Historical Institute of the University of Stuttgart is organizing the interdisciplinary project seminar “The Flexible House” as part of the subproject G2 “Successfully Failing.” On May 8, 2025, a group of students from the University of Stuttgart and FH Augsburg visited the MAN Steel House at the Hohenlohe Open-Air Museum in Schwäbisch Hall-Wackershofen.

On-site, the group received an insightful introduction to the prefabricated house from 1951, which was designed by the MAN company in response to the housing shortage after World War II. Particularly enlightening were the insights into the historical background, from construction methods to technical details, as well as the societal significance of the steel house and the history of the family who lived there. The opportunity for exchange among the students was also very stimulating, during which the Augsburg colleagues presented their previous designs and ideas for the exhibition planned as part of the project seminar. The stimulating discussion provided many new ideas and strengthened the interdisciplinary collaboration.

The visit to Wackershofen was not only enriching in terms of content but also a motivating step toward the joint exhibition concept. (Katharina Fink)

On 5 and 6 June 2025, the ‘Railway Bridges’ workshop took place at the NLD in Hanover as part of the Railway Bridges Cluster in the DFG Priority Programme ‘Cultural Heritage Construction’ (SPP 2255). For the fifth time, it brought together experts from Germany and Switzerland from DB InfraGO AG, SBB and the monument authorities to improve the exchange between research and practice. The focus was on an interim review of the railway bridge initiatives of SPP 2255: discussions centred on what has been achieved so far, where there are still problems and what further tasks are emerging.
In the first thematic block on 5 June, specific projects were presented. The objectives and work status of the second phase of the sub-project ‘Railway Bridges – Monuments in the Network’ and the database development at the Lower Saxony State Office for the Preservation of Historical Monuments were presented. Other contributions dealt with the load-bearing behaviour, test loads and static verification of arch bridges, as well as the ‘upcycling’ of the SBB Wipkingen Viaduct using new technologies.

The second day, 6 June, was mainly devoted to institutional developments. Presentations were given on the interim results of bridge renovations and maintenance measures in Hamburg in the context of the Bridge Advisory Board founded in the Hanseatic city, the newly established Monument Preservation Specialist Group at DB InfraGO AG, the DB InfraGO repair regulations with a focus on vaulted bridge maintenance, and current developments in the LuFV bridge construction programme. This was followed by a presentation of future prospects: a pilot project on historic railway bridges in Hanover, a planned application for a DFG knowledge transfer project in cooperation with DB InfraGO AG, and the preparation of a cross-state position paper on railway monument preservation on the initiative of SBB. The workshop concluded with a final discussion and an outlook.