Intensive residential densification: Impact on the urban morphology of Santiago de Chile

Areas of growing centrality in Santiago de Chile are currently under processes of residential densification, which vary in degrees of intensity and forms of impact in the urban environment. As a result of a weak conduction of residential densification, the structural-radical transformation of the urban fabric has resulted in the degradation of urban space. However, if well designed and planned, residential densification is a form of urban growth that can optimize infrastructure and allow the development of more complex and inclusive cities. This work aims to understand to what extent urban morphology shapes these urban transformation processes in 15 selected areas; the work also proposes typologies of residential densification based on the intensity of the process and the state of transformation of the urban fabric. Density (dwelling units/hectare) is understood as a systemic relation with parameters that determine urban compactness and configure public space such as lot subdivision composition, setbacks, building footprint and height, floor area ratio and mixed use index, among others. The study concludes that the impact of intensive densification on urban space can have three main effects: (1) The standardized high-rise tower radically fragments the urban fabric structure and skyline, to the extent that multiple and dispersed vertical operations transform lot geometry abruptly increase building height and lower land occupation; (2) this triggers a "residentialization" effect, unbalancing existing diversity of activities and contributing to undermine urban vitality; (3) which impairs the quality of public space, by introducing exogenous typological elements (such as setbacks) and reducing contact between private space and street space.