Profactor developed a new quadruple-glazed insulating glass unit with ultra-thin glass membranes together with LiSEC in the EU project "MEM4WIN". The project shows that insulating glass has through a lowering of the energy required for production and an almost doubling of the insulation value (U-value 0.3 W/m²K) the potential to contribute to significantly reducing energy consumption. At the same time, important characteristics such as durability, weight, sound insulation, aesthetics, energy generation (organic PV, integrated solar collectors), daylight control (micro-mirrors) and costs were improved.