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Glassplitter / Broken glass

submitted by

Annette Gigon Mike Guyer

Waste glass, as shown in the exhibition “Gigon/Guyer. Kirchner Museum revisited”, Davos 2022/2023. Photo: Seraina Wirz, Zurich

We are only vaguely conscious of the quantities of materials we throw away each day.

Near the end of the previous century, waste recycling became more common in Switzerland, not only for paper, but also metal and glass. While developing the plans for the Kirchner Museum Davos in 1989, we had the idea to use waste glass as a roof covering for the glazed building instead of gravel or sheet metal. Glass has a similar weight to gravel and is therefore well-suited to ballasting flat roofs. Without much effort, the cullet could be taken from the recycling process before remelting.

The unusual roof covering, in combination with a protective mat made from recycled tires, has served its purpose well over the years. Whenever the sun shines it continues to create a crystalline sparkle on the building’s ‘fifth façade’.

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Annette Gigon and Mike Guyer are architects who founded the architecture firm Gigon/Guyer in 1989. Among their oeuvre are both museum buildings, such as the Kirchner Museum Davos, and residential and office buildings, like the Prime Tower in Zürich. Their work has received numerous awards. Both partners have been full professors at ETH Zürich since 2012.


This object is part of the TACK Exhibition “Unausgesprochenes Wissen / Unspoken Knowledge / Le (savoir) non-dit”, in the section “Making and Materiality”.