Unifying and Decomposing Building Types: How to Analyze the Change of Use of Sacred Buildings

What do churches do? What do mosques do? Constructivist sociology has usually argued that buildings do not do anything, but are enacted by users. Conversely, actor-network theory has interpreted buildings as actants that are stabilized by architect-controlled networks. In this article, I argue for a differential theory of objects, which conceives of the specific agency of different kinds of objects. Buildings can be understood as mutable immobiles, objects that are immovable and thus likely to be changed on the level of their social classification, or in architectural terms, their building type. Drawing on fieldwork in and around Berlin, Germany, I use two different kinds of change of use to show the agency of buildings as mutable immobiles. First, I show that in the case of churches that are changed to other uses, the church attempts to discursively associate the buildings to religion primarily and then uses large scale interventions to preserve the unity of the church if change of use cannot be avoided. Second, I show that in the case of factories that are turned into mosques, very small material interventions with furniture change the buildings.