Social housing: residential segregation and settlement mechanisms

In France, social housing accounts for 16 % of all main residences. Its aims are twofold : to provide housing for modest households, and to favour residential diversity. Since 2000, with the introduction of the Solidarité et Renouvellement Urbain (SRU) law, we have observed a better spread of social housing among municipalities. Nonetheless, in the meantime, income segregation has not improved in large urban areas. This study seeks to understand this paradox by analyzing the settlement patterns within the social housing sector. We show that the public housing sector can contribute to reinforcing segregation within an urban area. The spatial concentration of social housing, partly inherited from the construction boom of the 1960s, remains a key structuring factor. But beyond the location of the housing itself, the spatial distribution of tenants according to their income level also plays a significant role in shaping residential segregation. Two mechanisms help explain this internal polarization. At the point of entry, social housing in the richest neighbourhoods is more likely attributed to the richest entering tenants. At the point of exit, while the better-off tenants in social housing tend to leave social housing more frequently overall, they are less likely to do so when their dwelling is located in a privileged area where conditions are favorable. These dynamics hinder its ability to promote social mix. A more balanced allocation of tenants could help mitigate segregation.