Energy Efficiency Ratings Explained

A Guide To Energy-Efficient Window Ratings

12 Jun 2023

If you have read our previous articles, you may have noticed that we have mentioned energy-efficient window ratings before. However, you may not fully understand what that actually means and we believe homeowners should be more aware of these ratings for many reasons. As a leading window supplier, we know everything there is to know about them.

For this article, we decided to bring it back to basics by discussing how energy-efficient windows are rated and how they can affect your home and your energy bills. Continue reading to learn how to choose the right energy-efficient windows for your home.

How Are Energy-Efficient Windows Rated?

The energy efficiency of windows is rated through a system called the Window Energy Rating (WER) to allow homeowners to easily compare the energy efficiency of different window products. In the UK, there are a few rating schemes, the most popular one being the British Fenestration Rating Council (BFRC), the British Standards Institute (BSI) and CERTASS. Each rating scheme works in a similar way. The rating system is based on a scale of A++ to E, with A++ being the most energy efficient and E being the least. 

A complex formula is used to calculate the letter rating. This formula takes several factors into account including the U-value, the air leakage and the solar gain of the window and the frame. The U-value measures how well it insulates against heat loss, the air leakage measures how much air is able to pass through and the solar gain measures how much solar radiation passes through. In other words, an A-rated window has a higher energy efficiency than a C-rated window. D or E-rated windows are not considered energy efficient and we don’t recommend them for use in the home.

Where Can You Find The Energy Rating?

Now that you understand the rating system, you will be able to read the energy rating of any efficient energy window product. A window’s energy rating is displayed on an official energy rating sticker or label, similar to the energy rating label found on a refrigerator or a washing machine. This sticker is usually found on the inside of the frame. Its purpose is to show official proof and provide you with product information including the name of the rating scheme, the letter rating on a large, coloured scale and the energy index. The label should also include the measurements of U-value, the air leakage and the solar gain of the window product.

Why Choose Energy-Efficient Windows?

When choosing windows for your home, it’s important to consider the energy rating, frame material and type of glazing. Installing energy-efficient windows can help homeowners save money on their energy bills over time by reducing heat loss, whilst also reducing their carbon footprint. For high energy efficiency, we recommend going for A-rated windows. In general, frames made from UPVC or timber are generally more energy efficient than other frame materials. In terms of types of glazing, triple-glazed and double-glazed windows are far more energy efficient than single-glazed windows. With that being said, it’s vital to have all windows installed by a professional. Poorly installed windows can cause air leaks, which decreases the energy efficiency of the windows, leading to higher energy costs. 

A Rated Windows In Stafford and Cannock

Are you looking for high-quality A-rated windows for your home? We have exactly what you are searching for at Conservatories and Windows Direct. We supply a superior range of energy-efficient windows in different sizes and styles to suit the exterior of your home. Our Optitherm A-rated windows help to reduce the amount of energy you need to heat or cool your home by 20%, reduce emissions and even decrease condensation by up to 80%, reducing the chances of mould and bacterial growth in your home. 

Whether you’re looking for Casement, Tilt & Turn, Sliding Sash or Flush Sash windows, we can help you choose the right windows for your home in Stafford, Cannock or the surrounding areas. If you want a free quotation from Conservatories and Windows Direct, please fill out our quotation form. For any enquiries on our window products, you can contact us by making an online enquiry or calling us on 0808 2223344


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