A superior technology designed to minimise energy loss through your windows
See also:
Building Regulations and Window Energy Ratings
Window Energy Ratings (WERs)

Window Energy Ratings (WERs) are used within the window industry and have a rainbow style label like the image to the left. High quality ‘A’ rated windows theoretically lose no energy through the window, and some installers offer this as standard. ‘A+’ and ‘A*’ ratings are also now available.
There are several competent persons bodies that endorse WER labels, the one to the left has been endorsed by the British Fenestration Rating Council (BFRC).