Objects redevelopment methods of the “gray belt” - industrial areas surrounding the historical district of St. Petersburg, Russia - have been considered. Information about 45 objects located in different administrative districts of the city was collected. Factors of physical wear (wear of floors, walls, roofs, types of building structural system) have been chosen as a criteria for clustering. As a result of the study, SOMs with different learning parameters were created as a result of the study. Energy efficiency calculations for two clusters were made with the selection of modern materials. Recommendations for the reconstruction according to the parameters of physical wear are given.