Pay more attention to the double -glazed window — filling the window frame. Its minimum thickness found in the market is 24 mm, but such a single -chamber double -glazed window is suitable only in the case when the window goes to the glazed balcony — there is absolutely no why to overpay. If you have the most ordinary apartment glazing, then it is better to opt for energy -saving windows with special heat -insulating double -glazed windows. Such glazing is available not only in Moscow; plastic windows from the manufacturer in g. Lyubertsy, Dolgoprudny and other cities near Moscow, are now also equipped with similar double -glazed windows.