Protective glazing: The conflict between energy-saving and conservation

Glazing is usually considered an important element in the conservation of energy in a building. Many churches In Switzerland (with windows dating mainly from the 19th and 20th century) have therefore opted for installing protective glazing. In addition to providing thermal insulation, this should protect the stained glass from the elements, and aid in its conservation.

This interdisciplinary research project seeks to answer the following questions: In how far does protective glazing fulfill requirements in terms of energy conservation, weather protection and aesthetics? How can the cost versus the benefits of such an operation be calculated and evaluated? How should subsequent costs be factored in, for example relating to the maintenance and lifespan of the protective glazing?

The main objectives of this project are to establish a new basis for evaluating protective glazing, taking into account current and future standards on energy, and to develop outlines for the overall, long-term protection of stained glass and its supporting elements. The results of the research are intended to aid church committees, architects and conservationists in evaluating the options available for improving the energy consumption of the building.

Project in collaboration with the Empa Dübendorf (Department of Building Technology), Baumann Akustik und Bauphysik AG (CH), the Association Professionnelle Suisse du Vitrail (APSV), and the cantonal and federal services for the preservation of historic monuments.

The project was financed by the Stiftung zur Förderung der Denkmalpflege, Zurich.

Final report of the projet (in German):
Report (PDF)
Annexes (PDF)