A variant of PE78N system intended for the constructions of a particularly high requirements for thermal insulation. Thanks to the special inserts there can be obtained very high thermal insulation.
In more insulated PE78N HI version – with closed glass chamber and insulating insert, the U_f frame heat transfer coefficient equals 0,9 W/m²K. In the most insulated (PE78N HI+) version – with closed glass chamber and insulating insert made of aerogel, the frame heat transfer coefficient equals 0,7 W/m²K.

Fillings 
Single or packed window panels with any kind of glass or opaque panels of width: 23-61 mm.