Fire scenarios may pose serious risks and induce severe damages to anthropic structures, activities and business. These can be represented by typical fires in industrial facilities or also atypical scenarios involving differentiated targets as in the case of interface fires. Risk assessment of atypical scenarios requires improved approaches since a multi-risk framework can arise including the interactions between the fire and surrounding domains. An effective hazard investigation and management should therefore include estimations of consequences based on the results of models simulation. The present study deals with a preliminary risk assessment methodology applied to fires interacting with an existing urban area. The fire spread is approached through a dedicated tool and a GIS (Geographic Information System)-based system used to spatially map expected consequences. Starting from these data, a preliminary risk estimation is proposed with the aim of mapping hazardous areas. In this sense, a combined approach based on fire simulation tools and exposure functions is employed. Major risk areas for specific targets are identified in terms of risk contours and expected results can be used to support land planning and emergency-related operations.