U6 – A triple glazed unit with high energy efficiency. Glass construction from outside to inside is 6H-Tg18Ar-4HT-Tg18Ar-33.2T. The outer pane is a 6mm toughened glass and an 18mm warm TGI spacer filled with inert argon gas. Also, the window has a 4mm centre pane which is toughened with a low emission coating. The 6.2mm internal pane is an anti-burglary class of laminate 33.2 (class P2A, EN 356,1(B)1 wg EN 12600), complete with a low emission coating. This glazing unit produces a U-Value of 0.70W/m²K.