In this article, we cover conceptual aspects related to social segregation and the urban characteristics that intensify it in Santiago. Then, we explain how our proposal provides guidelines to generate social integration, using Santiago's small housing estates as historical reference and model. Lastly, we discuss the social, urban-architectural, and economic aspects of the project, describing how urban borders make social integration possible, as well as the benefits and risks that different socio-economic groups face when sharing the same living spaces and urban context.