This study tries to understand what contextual elements increase the vulnerability of social housing inhabitants. Ten semi-structured interviews were conducted with social housing inhabitants in Montréal. Interviews highlighted that public housing is an inclusion mechanism, allowing people to have their proper home with a low rent. Nonetheless, it is also an exclusion mechanism, limiting its positive effects. Three main elements have been identified: hygiene and sanitary conditions, stigmatization and neighbourhood. They impact the overall health of their inhabitants. Maintaining their situation of vulnerability, they limit the improvement of their living standards. Therefore, these contextual elements are integral parts of mechanisms of exclusion.