„MatGlass“: Materiality and authenticity of glass and glass construction in the building of high modernity.
A structural and restoration science survey and analysis of materials and construction.
Content and aims
The materiality and authenticity of glass and glass constructions of buildings from the high modern era have not been the focus of basic research until now. In today's society, the significance of glass as a material has declined to such an extent that even monument conservators sometimes regard glass and glass constructions of secular buildings from the industrialization or high-modern era as disposable mass. The practice of replacing glass results in the irretrievable loss of important testimonies to the history of time and technology.
In order to counteract this situation, the project partners, the Institute of Building Construction at the TU Dresden and the Professorship in Materials and Preservation Science at the University of Bamberg, want to jointly establish a scientific basis on the subject of industrially produced glazing and its use in building constructions.
The project examines the period from about 1880 to about 1970 and thus covers the area of high modernism. With the High Modern period, an important time period is examined in more detail, into which two significant changes in technology fall: first, the transition from blown flat glass to drawn glass in the early 20th century, and second, the introduction of float glass in the 1960s.
The overarching goal is to manifest the importance of the original glass product as an indispensable and irreplaceable element of authenticity and thus of the cultural significance of buildings of high modernity. The living character of industrially produced glass from the time before the introduction of float glass is a result of the manufacturing processes. It is precisely this supposed deficiency that contributes to the fascinating duality and unique materiality of industrially produced glass: due to its translucent properties in the wavelength range of visible light, on the one hand it is transparent and disembodied, while on the other hand the light passing through is focused or scattered at the optical defects, creating a living structure. Due to the almost perfect nature of today's float glass, it completely lacks these characteristic properties. Therefore, when replacing historical glass, both authenticity and materiality are lost.
The aim of this research project is to identify characteristic construction types of glass elements from the industrialization period and to define methods for their recognition. This objective requires answering the following research questions:
- What are the main lines and innovations characterizing the use of glass and glass constructions in the building industry?
- How can material-specific and constructive innovations in glass technology and glass construction be identified, appreciated and communicated as elements constituting monuments?
Based on the research results, the aim is to create an increased awareness of historic preservation with regard to the preservation of historic flat glass. The goal is to provide historic preservationists with a tool so that the value of flat glass and glass structures can be recognized as significant elements of the authenticity of buildings in the study area and evaluated accordingly. To this end, an evaluation scheme will be created that focuses particularly on the original flat glass and glass construction of high modernist buildings.
Extensive literature research, mapping of exemplary buildings as well as minimally invasive and non-destructive glass examinations form the basis of the interdisciplinary collaboration in order to characterize and identify preserving glass inventories of the high modern era. For this purpose, the sometimes divergently used technical vocabulary is combined to form overarching definitions of terms.
The further development of glass manufacturing processes was accompanied by a development of the available glass formats, qualities and their safety properties. The extent to which technical innovations in glass production have led to changes in construction methods will be investigated. The focus here is primarily on innovative design variants that enabled slimmer constructions in favor of an increasing proportion of glass in the facade. Another focus is on the analysis of the typical building construction requirements of the time placed on the glass. This consideration is linked to the development of glass processing to increase load-bearing capacity and safety.
A geographical as well as chronological classification of the glassworks and glass processing plants including the logistical boundary conditions and the associated ranges is also aimed at in order to be able to estimate the availability of the glasses. On this basis, historical flat glasses in existing buildings are classified with their location and construction period. In the course of this, a narrowing down of the specific inventory to individual manufacturing processes becomes possible.
Currently, there is no canon of methods with which glass can be assigned to the different manufacturing processes. Therefore, different evaluation and measurement methods are developed and disseminated to characterize the production-related features, such as optical, visible and point defects, and to determine the respective material compositions. The core of the optical investigation is the determination of the materiality of the glasses from the period of high modernity.
Prof. Dr. ir. Christian Louter
Dipl.-Ing. Franziska Rehde
Prof. Dr. Bernhard Weller
The project is funded by The German Federal Environmental Foundation (Deutsche Bundesstiftung Umwelt DBU) within the framework of the DFG Priority Program 2255 „Cultural Heritage Construction (Kulturerbe Konstruktion)“: