The principle of “intercomness” – mutual penetration and visual merging of the space of streets with the space of the trading floor is widespread with us and abroad. Recently, it is increasingly wider and wider in solving our large highways (for example, shops on Kalinin Avenue in Moscow and on Lenin Street in Riga). The transition from a 6×6 m mesh to a 9×9 m networks and 12×12 m leads to an increase in the cost of the frame by 6-10%, and the buildings as a whole by 2-4%, but the power of the enterprise increases by 8-10%due to the more intensive use of the area. Thus, the transition to buildings with large nets of columns is economically justified. In addition, in trading halls with a 6×6 m mesh, the possibilities of maneuvering changes in the arrangement of equipment are limited, which is practically necessary with seasonal changes in the profile of commodity sections and departments and it is extremely desirable, in terms of possibility, by updating the interior at minimal expenditure of forces, means and time. Finally, the use of a 6×6 m column grid in large trading buildings sharply reduces the architectural expressiveness of the halls, which are, as it were, divided into narrow corridors in rows of often standing columns. Obviously, when developing projects of large trading buildings for construction in the next decade, designers will focus on large spans 9×9 and 12×12 m. At the same time, work will begin on the wide implementation of structural systems, allowing in multi-storey buildings re-transmitting: cover spans at 24-30 m. With the solution of this technical problem, the construction of “non -focal” multi -storey buildings of department stores will be opened “Green Street”. In the search for rational structural systems that allow the best way to solve the issues of engineering equipment, architects and designers proposed to apply crazy floors in retail buildings.