Glass blocks have been rated for their energy efficiency by the Windows Energy Rating Scheme and have been shown to outperform windows in energy savings for both cooling and heating.

The Window energy rating scheme (WERS) is conducted independently to rate the annual energy impact of windows and other glass products in a house and assists in the selection of the most energy efficient windows and glass.

Energy efficient windows offer significant benefits to home owners. In addition to reducing energy costs and green house gas emissions, a properly selected window plays an important role in improving comfort and well-being.

The WERS scheme operates on three levels to convey information about the energy performance of custom-rated windows, glass block panels and skylights:
•    Star ratings for heating and cooling
•    Indicative % reduction in heating and cooling needs and interior fading damage
•    Thermal, solar and optical performance data

WERS Silicon certificateWERS Mortar certificate