Paulo CHARRUADAS / Philippe SOSNOWSKA
(Université libre de Bruxelles)

Abstract: Except religious and aristocratic buildings, most of the constructions and houses in the first ages of the former European cities and towns are made of cob and timber. The gradual transformation of this architecture in stone and brick constructions – the so-called “petrification” – is one of the most important processes within the cities and towns. Nevertheless, until now, this phenomenon has been little studied by historians and archaeologists (for instance Lilley 2002; Schofield & Vince 2005; Clark 2009). Therefore, the modes and chronology of these progressive architectural transformations are still uncertain.
“Petrification” is a significant process that makes it possible to approach a new range of important issues in urban history. It concerns the general aspect of the cities and towns and stands for an obvious change of the landscape and the evolution of material culture. From a social viewpoint “petrification” changes the way in which houses are in contact with each other and it consequently modifies town politics as well as the relationship between neighbourhoods. In conclusion, “petrification” changes deeply the urban life. From an economic viewpoint the “petrification” process has important implications on the organisation of urban supply of building materials. The town-countryside relationship progressively evolved: suburban forests, clay deposits and stone quarries are form now on subject to control attempts and new management strategies. In the same way the urban market connections with regional and international trade flows also change to meet the new urban needs concerning buildings.
By integrating the different viewpoints of this complex issue we propose to elaborate a new methodology taking the former city of Brussels (duchy of Brabant then former Low Countries) as example : building archaeology data will be combined with dendrochronology, dendrology, radiocarbon dating and rereading of historical sources in order to bring further clarifications and to go beyond the traditional architecture history.

Keywords: Brussels, building archaeology, history, petrification, building materials