The Window Energy Rating Scheme (WERS) is managed by the Australian Window Association. It provides a system for rating and comparing the energy performance of windows and doors against one another, in a similar fashion to the rating system commonly used for white goods. To participate in WERS, window fabricators must obtain energy ratings for their products from a rating organisation accredited by the Australian Fenestration Rating Council (AFRC) and rated windows must meet all relevant standards. In order to determine window performance data, WERS uses a window’s U Value and Solar Heat Gain Coefficient.

In simple terms, the U Value is a measure of the rate of heat transfer through a window. The lower the U Value, the better level of insulation the window provides.

How Do Star Ratings Work?
Star ratings rank the window against alternative products using a ten star scale, based on 17 ‘generic’ window types. The generic windows range from very low performance to very high performance for heating and cooling and apply to the whole window – glass and frame combined. A low star rating indicates a window is a relatively poor performer, while at the other end of the scale, ten stars indicates the perfect theoretical window. In reality, the highest performing windows available in Australia fall generally between 6 and 7 stars for heating and between  and for cooling. Capral is proud to confirm that it has a number of window options in these ranges.

For more information on star ratings, visit the WERS website:

WERS Certificate
Each individual WERS rated product has its own WERS certificate. WERS certificates include information that can help you select the best windows and doors for your home. As well as the product’s star rating for heating and cooling, certificates feature a brief product description, performance rating data and the potential heating and cooling improvements when compared to a single glazed window.