Michael Obrist
in conversation with
in conversation with
Stefan Rettich
Die obsolete Stadt – Wege in die Zirkularität
Wohngespräche
02. Dezember 2025
Stefan Rettich
Michael Obrist [feld72] in conversation with Stefan Rettich about "Die obsolete Stadt – Wege in die Zirkularität"
From shopping centres and cinemas to churches and gas stations – more and more types of buildings are falling into disuse. This development is driven by the megatrends of digitalisation, transport transformation and changing religiosity. A wide range of conversion projects already demonstrate the circular potential of these obsolete types of buildings. Against the backdrop of planetary boundaries, these obsentials must not be allowed to be demolished. Rather, the obsolete becomes a prerequisite and a crucial resource for circular development. A change of perspective from a construction revolution to an urban revolution is essential, because it is not enough to repurpose building after building without looking at the big picture. Twelve principles of the circular city show how this can be achieved.
The lecture will highlight the background to this transformation in the building landscape of cities and the opportunities it offers for curbing land speculation and promoting the common good – including solutions to the housing shortage. If the politically responsible institutions face up to their responsibilities, obsolete systems could become a sustainable source of positive change.
Stefan Rettich
Stefan Rettich (1968) is an architect and professor of urban planning at the University of Kassel. From 2011 to 2016, he was professor of theory and design at Bremen University of Applied Sciences, and before that he taught for four years at the Bauhaus Kolleg in Dessau. He is a founding partner and co-owner of KARO architekten.
karo-architekten.de
From shopping centres and cinemas to churches and gas stations – more and more types of buildings are falling into disuse. This development is driven by the megatrends of digitalisation, transport transformation and changing religiosity. A wide range of conversion projects already demonstrate the circular potential of these obsolete types of buildings. Against the backdrop of planetary boundaries, these obsentials must not be allowed to be demolished. Rather, the obsolete becomes a prerequisite and a crucial resource for circular development. A change of perspective from a construction revolution to an urban revolution is essential, because it is not enough to repurpose building after building without looking at the big picture. Twelve principles of the circular city show how this can be achieved.
The lecture will highlight the background to this transformation in the building landscape of cities and the opportunities it offers for curbing land speculation and promoting the common good – including solutions to the housing shortage. If the politically responsible institutions face up to their responsibilities, obsolete systems could become a sustainable source of positive change.
Stefan Rettich
Stefan Rettich (1968) is an architect and professor of urban planning at the University of Kassel. From 2011 to 2016, he was professor of theory and design at Bremen University of Applied Sciences, and before that he taught for four years at the Bauhaus Kolleg in Dessau. He is a founding partner and co-owner of KARO architekten.
karo-architekten.de
