Halo has launched its latest addition to the System10 range – the TwinSash – which is said to achieve the lowest Uvalues and sound reduction of any PVCu window on the market today. The TwinSash's U-value performance ranges from 1.2 down to an industry-leading 0.38, Halo claims, depending upon the type of glazing, spacer and gas used. The 1.2 U-value …