The window-wall unit contains a window box, the parts of which, which are adjacent to the inner surfaces of the window slot of the wall, ensure that all these surfaces are completely covered by the window box. One row of glazing is formed by one sheet of glass or glued single-chamber construction-grade double-glazed glass with a thickness of 16 to 24 mm. The second row of glazing is formed by glued single-chamber glass with a thickness of 16 to 24 mm. A row of glazing formed by a sheet of glass is placed on the inside of the window. The distance between the specified two rows of glazing ranges from 160 mm to 240 mm. The parts of the window frame, which are adjacent to the inner surfaces of the window slot of the wall, are made in the form of profiled beams made of polymer material, the inner cavities of which are filled with heat-insulating material with a thermal conductivity coefficient of no more than 0.05 W/mk. The part of the window box, which is adjacent to the upper inner surface of the window slot of the wall, is made reinforced inside with the provision of rigidity on bending of the jumper to take the load from the wall above the window.