"This paper deals with changes in the built environment caused by the economic crisis and housing market development. Social polarization of the population affects St. Petersburg's built environment. After repairs, rich tenants buy comfortable apartments in the housing in the historical centre or cottages. Rich people congregate in isolated settlements in the suburbs and subdistricts of the city centre. These sectors are dissonant with the other urban districts, which gradually turn into slums because municipal authorities have no finances for new buildings and renovation. The main part of the city's residents have no opportunity to improve their housing conditions. They remain in delapidated housing in the city centre or migrate to cheap apartments on the outskirts. At present, St. Petersburg's built environment represents a set of "isles" for the rich and slums for the poor, while the rest of the housing stock undergoes a polarization process. Negative changes in the built environment make it necessary to work out mechanisms of housing management adapted to economic and social conditions. It could combine elements of state regulation with the housing market."