This article is devoted to the issue of rational exploitation of space in cities with a large population. It is known that a sharp decrease in the area of land plots within the city limits accessible to public use leads to a decrease in the quality of life of citizens. The authors of this article are considering in detail the possibility of using roofs as additional public spaces. The article discusses such methods for using roofs as solar power generation, rainwater harvesting, apiaries and poultry farms, sports complexes, playgrounds, vegetable farms, etc. Particular attention is paid to the so-called ""green roofs"", their design, classification, application. The authors of this article talk about the numerous advantages of green roofs, such as the ability to manage wastewater, reduce the influence of “urban heat islands”, create new public spaces, create new jobs, increase energy efficiency, reduce noise, increase market value, etc. However, the authors of this article did not forget to show the disadvantages of green roofs. The main disadvantages of this project are the higher initial cost, the increased load on the foundation and walls, and the increased costs of operation. Nevertheless, the authors draw conclusions that the advantages of green roofs far exceed their disadvantages and the further development of this direction is very important and promising. 3. Installation of active seismic resistance monitoring systems (active method). Such an active feedback control system contains three main elements: a. Sensors for measuring external excitation; b. Computer hardware and software; c. Drives to provide the necessary control forces. At present, the most popular is the hybrid method of semi-active control, which combines the advantages of a seismoisolating basement with passive shock absorbers, which is much more economical in comparison with the active method.

Keywords: city, roof in operation, green roof, dense urban development, energy saving, ecology, green building, green building