Flat Roofs Characterization in Barcelona's Historic Center

Historic centers usually have a dense urban fabric and little availability of open public space. After the covid19 pandemic, this lack has become even more apparent. In this context, the communal flat roofs of the buildings can represent an important potential to improve the quality of life in dense historical centers. Specifically, in the case of Barcelona, the project in which this research is framed studies how to use them as space of care, meeting, and rest specially addressed to the increasingly aging population. Prior to any action of rehabilitation or modification of existing roofs, their characterization is necessary. This paper presents an in-depth constructive description of the existing roofs in the historic center of Barcelona, never been done before. The different periods of construction show different solutions present that are described in this analysis, detailing the materials originally used and quantifying the main properties of the typologies that influence their behavior. These solutions are georeferenced and quantified in the historic center as a whole. The main interventions usually carried out are also described and geo-referenced. Finally, guidelines and aspects to consider for its rehabilitation for future use are provided, also quantifying the available potential of community roof surfaces that could assume new uses as communal space for citizens.