The article analyzes the effect of location on the margins of the city on the living conditions of households in outlying districts of Brazzaville, focusing on the constraints related to daily mobility and household functioning. The results of the study show that urban households, faced with housing problems (high rent costs, lack of access to social housing, etc.) in the central and pericentral districts, carried out a residential relocation at the margins of the city driven mainly by the search for low rental costs and land to build to become homeowners. Settling in unplanned areas lacking most basic social services and infrastructure places households in a situation of sometimes remarkable vulnerability.