BREEAM (BRE Environmental Assessment Method) is a widely used environmental assessment method for buildings, founded in UK. It describes a building's environmental performance and sets the standard for best practice in sustainable design. Credits are awarded in several areas according to the performance of the system. The environmental impact of all building components is rated according to a life cycle assessment LCA of the product.

All specifications are described in the book ‘the green guide to specification’. As a standard for aluminium powder coated windows, the rating is situated between B and E. Yet, Reynaers' systems Eco System and CS 68 achieve a summary reference of 'A'-rating within health, industrial, commercial, retail and education schemes.