Josef GSPURNING
(IGR University of Graz, Graz, Austria)

Abstract: In 1999 the almost gap-less and beautifully preserved roofscape of the old town center of Graz has been one of the most important reasons for conceding the status of an UNESCO World Heritage Site to the city. But, despite its importance in local, regional and even global scale and although the roof from authors typically is addressed as the fifth façade of a building which is significant for a town’s character in a crucial way, the expression “roofscape” (or its German pendant “Dachlandschaft”) often is defined by terms taken from architecture, artistry or legal regulations. In contrast the approach proposed within this paper doesn’t understand roofs as an expression of a mainly functional set of characteristics or as a zone of colliding planning interests (for example solar potential versus protection of historical buildings). Instead of that the means of Geographical Technologies (basically GIS and RS concepts) are employed to derive an unbiased definition of roofscape and emphasize it’s identity by specific criterions like shape, colour, raw materials as well as texture, elements of patchiness and roof ensembles. Besides, the usage of GIS and RS elements enhance the underlying research design not only with new technology (i.e. spatial toolboxes for delineation of a roofscape) but also with new data types (i.e. laserscanner data) and metrics for describing the investigation outcomes. The results of the work described in the paper could be summarized in the following manner: Delineation and characterization of effective roofscape areas, design of a problem-oriented data model, implementation of this 3d spatial database and visualisation of the findings.

Keywords: roofscape, GIS, spatial database