Thermopanes with 2-layer glass or 3-layer glass. The best insulating double glazing is with 3-layer glass, also called super low-energy glazing. What insulates well in a double-glazed window is the space between the panes. The best U-value is obtained by using argon gas and a gap of 15mm. If you want a burglar-proof and personal-proof double glazing, choose toughened or laminated glass. Tempered glass is many times stronger than ordinary glass. Laminated glass is 2 pieces of glass tightly glued together with a foil in between. This foil holds the glass pieces in place should the window break, as well as making it very difficult to break through. |