Sustainability of traditional wooden roofs in Switzerland

Explore alternatives and provide support to homeowners, craftspeople, and cantonal and national institutions to promote traditional wooden roofing with a focus on sustainable development.

Factsheet

  • Lead school School of Architecture, Wood and Civil Engineering
  • Institute(s) Institute for Building Materials and Biobased Products IBBM
  • Research unit(s) Wood Modification and Gluing Technology group FGHV
  • Funding organisation Others
  • Duration (planned) 01.08.2023 - 31.01.2026
  • Project management Patricia Granado Sanzovo
  • Head of project Prof. Dr. Thomas Volkmer
  • Project staff Marcel Schnyder von Steegen
  • Partner Parc naturel régional Gruyère Pays-d'Enhaut
    Fonds Landschaft Schweiz
    Amt für Kulturgüter des Kantons Freiburg
    Division monuments et sites, Kanton Waadt
    Berner Heimatschutz
    Association Romande des Tavillonneurs
  • Keywords Tavillons, wood shingle, autoclave-treated wood, traditional roofs, wood cladding, anseilles

Situation

Tavillon (wood shingle) roofs are a traditional form of roofing with a rich heritage and high environmental, ecological, and artisanal value. Today, this technique is faced with the diminished durability of wood, as well as competition from other materials (tiles, sheet metal, synthetic materials) and modern methods (chemically treated wood through autoclaving), which guarantee increased durability. Some factors that influence the longevity of natural wood are rising global temperatures, increased variability in temperatures and winter weather conditions (alternating exposure to snow, rain, sun, hail), and more frequent extreme weather events. These materials and methods prove to be financially appealing, but have a negative impact on the economy, the landscape, and the environment. Solutions for improving the sustainability of wood are increasingly requested by customers affected by climate change, particularly in alpine regions where the trend threatens to worsen over the next few years. The exemplary nature of wood cladding seems to be under debate in various regions of Switzerland. This situation has encouraged partners to launch a research project to promote the use of wood in roofing, in terms of its impact on the environment, the landscape and the local economy, and to develop alternative approaches to improve the sustainability of wood.

Course of action

For the first stage, we will focus on various industry leaders, the production line, the market for wood shingle roofs, the practices and products used in autoclaving and, finally, its overall impact. With this in mind, the project will draw on surveys completed by the owners of buildings with wooden roofs and tavillonneurs (wood shingle roofers). We will also use information gathered from the autoclave industry and analyse the environmental impact of products on the market. A second phase will concentrate on the exploration of alternative techniques to the current chemical process of autoclaving wood in order to reduce the impact on the environment and the landscape. The project will also be based on a comparison of the environmental impact of the various techniques via the analysis of the life cycle of wood shingle made from natural wood, autoclaved wood, and synthetic tiles. The final objective of this project consists of developing a guide with clear directives and recommendations for best practices for the use and conservation of wood cladding at different sites across Switzerland.

Schindeldächer sind eine traditionelle Form der Gebäudeabdeckung.
Schindeldächer sind eine traditionelle Form der Gebäudeabdeckung.