An algorithm was developed and a program was written in the JavaScript programming language that determines the time for cooling the premises to 0°C when the heating is turned off in the winter. The calculation algorithm takes into account the loss of thermal energy through the outer walls and windows through the processes of convective and radiant heat transfer. The calculations were carried out for brick elite and standard Stalin and Khrushchev houses. When carrying out calculations, it was found that in the central premises of brick Stalinist and Khrushchev houses, the time to reach 0°C when the heating is turned off in winter increases by several hours when replacing standard single-chamber double-glazed windows (the total thickness of the double-glazed window is 24 mm) with standard double-glazed windows of the same thickness. The calculations also showed that in the corner rooms of brick houses, the replacement of standard single-chamber double-glazed windows with standard double-glazed windows with a total thickness of 24 mm practically does not increase the cooling time of the rooms to 0°C. If double-glazed windows with a total thickness of 44 mm are installed in the corner rooms (in these double-glazed windows the width of the air gap between the glasses is 16 mm), then, depending on the type of house, the freezing time of these rooms increases by 2-3 hours. Calculations also showed that the installation of two-chamber double-glazed windows with a total thickness of 44 mm creates a greater thermal effect in the corner rooms than laying a side window of the room with a brick over the entire thickness of the window opening.