The study is aimed to provide a detailed knowledge database of the housing sector in the period of real estate significant expansion in Bologna in the second half of the 20th century. The final objective is the definition of a digital archive that is accessible and searchable and also a tool for analyses before interventions. The first phase of this research has focused on consulting cartographies and archival documents. On the one hand, analyzing maps and aerial photos of Bologna has identified the urban sprawl in the reference period 1940-1970. On the other hand, the cataloguing from new building permits provides some relevant data about architectural and construction features of the housing sector in the same period. The data resulting from archival research are implemented with a municipal georeferenced database using GIS software. In this way, a direct link is created between building specificities, urban fabric, and localization, so that the shifting from the urban scale to the building one is always possible. Then, another purpose is the definition of an algorithm to identify a sample of residential lots suitable for replacement within the urban perimeter of the city up to 1970. An evaluation method is currently ongoing to assess the convenience of this intervention category, rather than restoration, and to define a protocol to support the decision-making process together with a management system in three areas (technical, social, and economic) respecting circularity.