High Performance IGU
IGU made of two or multiple sheets of glass separated by a spacer bar along the edges. The space between the sheets is filled with an inert gas like argon, crypton or xenon. The inner glass has a thin metal coating facing the space between the two sheets. The property of this metal coat is to let in the short wave sun energy from the outside, whereas it reflects and thus keeps in the long wave heat radiation from the inside. In this way an energy saving IGU keeps in the heat better than a traditional IGU without a metal coat.