Determining the actual solar potential for applications in the complex urban environment is a difficult task, particularly when there is a lack in background information, such as the texture and structure of the urban landscape, as this was until very recently the case in Greece. In this paper a simplified yet effective methodological approach for the evaluation of solar architecturally suitable areas of flat roof surfaces on typical multi-storey, multifamily buildings is presented. It is based on a statistical calculation model for solar potential that has been validated, by analysing actual measurements carried out in the city of Thessaloniki in Northern Greece. The model can be either used by private engineers or it can be alternatively incorporated in geoinformatics decision-making tools, such as GIS, to aid planners, regulators and developers to determine the solar potential. Finally, it is of great interest to notice that the PV potential of the multifamily buildings considered in the validation, proved to be rather poor. The solar utilization roof factor in the majority of the examined building cases was approximated only between 25 and 50%. (C) 2013 Elsevier B.V. All rights reserved.