Window Energy Ratings

Here at JG Windows we only produce ABC rated windows to ensure the highest quality for your windows, we know this might not mean much to you but read a little about how they are rated and why and hopefully this will help you make an informed decision.


Window Energy Ratings tell you how energy-efficient your windows are.  The rating system is based on a scale of A-G, with A-rated windows being the most energy-efficient.  The scheme is similar to the energy ratings you will find on household appliances, white goods and light bulbs.

Considering the fact that up to 25% of the heat within most homes escapes through the windows, it’s easy to see why more and more people are opting for A-rated windows.

Window Energy Ratings and A-rated windows are not new ideas nor are they simply British ideas. Window energy rating programmes are already in place in the USA, Canada and Australia & New Zealand as well as other countries. Many other countries are already working on similar schemes to provide energy rating of windows and doors.

The reasons for this are obvious: buildings are one of the major users of energy and one of the potential areas of losses in any building is via the glazing. Improving the energy efficiency of windows and doors gives large and lifelong improvements in the energy efficiency of buildings. This has a direct and quantifiable impact on energy-use. Energy-usage is not simply a British problem and countries all over the world are using Window Energy Ratings to improve energy-performance and select A-rated windows for the application.

Window Energy Ratings are not only for cold climates either – in the warmer areas of the USA and Australia the idea of Window Energy Rating is also important, except here the best window is one which rejects the solar heat gain and minimises the heat transfer into the building! This reduces the need for air-conditioning (a major energy-user in these areas) by keeping the building cooler. Window Energy Rating is indeed a “tool for all seasons”.

In Europe there are many similar schemes either starting or being developed and the UK is leading a project to develop a European wide Window Energy Ratings system.