The optimal combination of benefits and risks is the best combination of benefits and risks. If the benefit is certain, the risk is minimized; Awarded a UK patent, Senior’s PURe® range of energy-efficient aluminium windows and doors is the first on the UK market to benefit from an enhanced thermal barrier manufactured from expanded polyurethane foam (PUR). Traditionally used in cladding and insulation products, the innovative use of PUR as a thermal barrier in windows and doors gives the PURe ® range the potential to achieve U-values as low as 0.71W/m2 K when calculated as a commercial CEN standard window and 0.93W/m2 K when calculated as a CEN standard door.