Energy Ratings

As anyone who works with windows will know, there’s more to them than meets the eye. Specifically, a customer will not be able to see with the naked eye quite how much heat can be lost through a poor quality window – although they may feel a draught!

As we all become more energy conscious, both in response to rising prices and concerns for the environment, Energy Efficient Windows (EEWs) have come into their own. So here’s our guide to Energy Ratings as commonly used in the industry.


What is the BFRC? 

The BFRV is a UK-wide system for rating Energy Efficient Windows. BFRC stands for British Fenestration Ratings Council.

Who runs the BFRC?

The Glass and Glazing Federation took over the BFRC in 2005. Since then it has worked hard to increase awareness of what the BFRC stands for and to encourage a wider acceptance of Window Energy Ratings (WERs). This has led to a larger number of licences and licence holders and to government acceptance of WERs, which means they are now used to help companies comply with building regulations.

How do Energy Efficent Windows ratings work?

EEW ratings are displayed in a simple traffic-light style, which has bee designed to be easily understood by the consumer. The ratings run from A to G, with A representing the most energy efficient systems. Because the guidelines are similar to those used on household white goods, most people will already be familiar with them.

Every window that has been rated by the BFRC has its own unique label, displaying the relevant information. The BFRC lists this as being:

  1. The rating leave – A, B, C, etc
  2. The energy rating e.g. -£kWh/(m2K); in this example the product will lose 3 kilowatt hours per square metre per year
  3. The window U value e.g. 1.4W(m2K)
  4. The effective heat loss due to air penetration as L e.g. 0.01 W/(m2K)
  5. The solar heat gain e.g. g=0.43

What are the benefits of the top ratings?

A high rating will help to contain and conserve heat within a home or other building, white allowing the sun’s warmth to contribute towards heating the home. It will also provide a barrier to wind, reduce condensation and improve sound insulation. Since 25% of heat in an average home is lost through the windows, it makes sense to install A-rated windows with energy efficient glass.

What materials are suitable for EEW frames?

All of the usual frame materials can be used for Energy Efficient Windows: aluminium, PVC-U, steel or wood.

Will customers understand WERs?

Consumers are already familiar with the ‘rainbow’ labelling on white goods such as fridges and washing machines, which represents energy efficiency. By following a similar labelling system for windows, WERs can help consumers more easily understand the level of thermal performance offered.

How does using BFRC ratings benefit the manufacturer?

By registering Energy Efficient Windows on the BFRC scale, companies can supply consumers who are increasingly looking to buy windows with BFRC ratings. They can also reap the benefits of the Glass and Glazing Federation’s activities, which include lobbying the government on policies and legislation, and offering support to help companies market their windows and boost sales.

What is Sash UK’s approach to Energy Ratings?

Because environmental concerns and energy efficiency are at the heart of the company, Sash UK has long been committed to taking a responsible approach to promoting Energy Ratings. The company aims to provide customers with energy efficient solutions and the latest ‘green’ innovations, so that they can live and work in homes and buildings that offer the best environment.

Sash UK is ISO 14001 accredited – this represents environmental management, showing that the company identifies and controls its environmental impact and constantly looks to improve its environmental performance. All Sash UK windows are BFRC accredited from C to A for energy efficiency.