The upper sash opens along the horizontal axis of rotation, which is located at the very top of the window, while the lower sash opens along the lower axis, which is located at the very bottom of the window. It is still important to note that in the course of opening the lower sash the process of nullif by the side railing is launched. As a result of opening all the wings of such a window, a small balcony is obtained. At the moment, the production of attic windows with an enhanced design and generally with more advanced operational characteristics has been established. More precisely, such windows are characterized by higher thermal insulation indicators. From the part due to the fact that special inert gas is pumped between the glasses of their double -glazed windows, and not just dry air.