77IWE Open-Out Window

High performance window in a lounge

77IWE Open-Out Window

Our highest performing window, the 77IWE Open-Out Window System is ideal for new build and refurbishment developments. The versatility of the system also makes it suitable for use in both high-rise and low-rise buildings. The system has been specifically designed to meet the most demanding British and European performance requirements in terms of thermal, weathering and security.

For optimal design flexibility, the 77IWE is available in single or dual colour options, including any RAL colour and anodised finishes


The system is available in a wide variety of configurations, delivering high levels of thermal performance through incorporating technologies such as high performance polyamides, insulated centre seals and profile foam insertions. The 77IWE system also fully integrates with our aluminium curtain walling and door systems.

Technical data
U value W/m²K 0.8-1.2 W/m²K
Air tightness (Pa) Class 4 (600Pa)
Water tightness (Pa) Class E1050 (1200Pa)
Wind load (Pa) Class C5 (2000Pa)