Your windows are one of the first things that people will see when they come to your home, which is why many of us want to make sure they look their best. So what if you could have beautifully finished windows that are energy efficient too?

As experts in energy-efficient windows, we have listed some of the features of energy efficient windows that help to explain how they work and why they are great for your home.

Energy-Efficient Glazing

In comparison to single glazing, or even the older style of double-glazing, energy-efficient glazing has the added bonus of a special coating. This coating is called Low E (Low-emissive) which is an invisible metal or metallic oxide coating that reduces the amount of heat that can escape through your windows, acting as insulation to trap heat. The coating is completely invisible, meaning that you cannot see it from the inside or the outside of the property.

Slim Double Glazing & Gas

Traditional double-glazing typically uses argon gas in-between the layers of glass. However, if you choose slim double glazing for your home or period property, we use krypton gas which has better insulating properties. Krypton has a higher level of energy efficiency due to the fact that it has a greater density and therefore better at reducing heat loss in smaller spaces.


Up to 80% of energy lost through a window occurs at its edge. The spacers that are used in traditional double-glazing are usually made from aluminium, which may not be the best for trapping heat. Instead, double glazed windows that use warm-edge spacers have a warmer internal edge temperature by up to 65% that helps to improve the energy efficiency of the window, as well as reduce the risk of condensation.

Picking The Right Frames

You might not realise, but the frames that are used when the windows are installed can have a big effect on how energy efficient they are. For example, older style metal frames are known to let out more heat compared to newer PVC-U alternatives.

However, there are more options available that can be just as energy efficient, if not more, which is especially useful to know if you are looking for a particular material to compliment the look and feel of your home. Here at Envirosash, we make custom, hand-made, frames from Accoya wood which is energy efficient, durable and environmentally friendly.

It is important to speak to an expert in window installation to ensure that you have the right frames for your property.

What Benefits Do They Have?

Energy-efficient windows have a range of benefits not only for your home but for the world around you too. They give you:

  • Smaller energy bills
  • A warmer home
  • A quieter home
  • Reduced condensation

Not only this, but having energy-efficient windows will reduce your carbon footprint too. Something that is important for us all to consider.

Can You Have Energy Efficient Windows In Your Period Property?

Just because you live in a period property, it doesn’t mean that you can’t benefit from energy efficient windows. There will be restrictions on what you can do to the windows that you have, however, there are other less intrusive options that you can consider.

It is important to not only speak to your local council but also an expert in period window installation too. To find out more about the restrictions you may face, visit our article on updating Grade 1 & Grade 2 listed windows.

Envirosash provides high quality sash window restoration services to London and the South of England. We restore, draught proof and install slim double glazing into existing period windows and doors. We also manufacture bespoke made to measure windows and doors, all our joinery is crafted from Accoya wood.

Contact Alex on 0800 292 2309 today to arrange a free survey and quote with no obligation.