We all know how important it is to have energy efficient windows and doors. Not only is our comfort at stake if our homes suddenly become a lot colder in the Winter, but our heating bills will rise as we try to rectify the issue. We also have a responsibility to look after our planet, so new products must now help homes conserve energy and reduce heat losses through the glazing. Here are some of the top ways to assess the energy efficiency of your existing windows, as well as any new windows you’re considering.

Here are some of the best ways to assess the energy efficiency of windows. Includes looking at your energy bills, comparing energy rating labels & finding out more about the u-values. Speak to a window installer for advice.Rising Energy Bills

Don’t underestimate your own instincts about whether your windows are letting in the cold. Do you find yourself turning on your heating before everyone else? Are your energy bills higher than others in similar properties? While it’s always important to do a price comparison, perhaps you have old fittings which let in draughts and you know they probably need replacing with modern products.

Hesitating to Replace?

Consider why you’re reluctant to get your windows replaced. Reputable companies will offer free consultations and quotations with no obligation to commit to further services, so it’s worth investigating the costs involved. There are also plenty of products with advanced functionality and energy performance ratings which are in keeping with traditional property styles. So if you’re worried about losing the heritage feel of your home, it’s time to start busting some of those myths you’re holding onto.

Window Energy Ratings & Labels

Always check the energy labels for windows. These are the rainbow coloured charts you see which come with new products and provide you with information about where the windows fall on the spectrum. This helps homeowners to compare different windows available, and the energy rating is assessed using multiple factors such as thermal transmittance, solar gain and the glazing installed. The most energy efficient windows will fall into A rated or A+ rated categories with this decreasing along the scale as you get further down the alphabet.


Another piece of data to check when assessing the energy performance of a window is the u-value. The lower this is, the better. It refers to how insulating the design and materials used are and the rate of heat transference through the product. To comply with building regulations, new and replacement windows must have a u-value of 1.6 W/m2K or below, but your supplier can point you towards the best performing products if this is high on your list of priorities.

Finding Energy Efficient Windows & Doors

Here at Merton Windows, we offer an extensive range of windows and doors. Providing the highest levels of quality and security in all the products we supply and install, we ensure energy ratings are completely clear, and we can talk you through our most thermally efficient products available. We work across Surrey and London areas, including Clapham, Mitcham and Ewell. Contact our friendly team now for a no-obligation chat about what we can do to improve the energy efficiency of your home.