Posted on: July 20, 2016

Installing Double Glazing In Your Sash Window

It’s quite common to find sash windows on listed properties or in conservation areas which can limit the changes you can make to your property. Even if this isn’t an issue for you, sash windows still add to the building’s character and can significantly reduce the value of your home if you removed them.

Despite their appeal, sash windows can be more prone to draughts so it’s essential to find an effective solution for keeping your home warm. There are a number of options to do this including installing double glazing in your sash windows, draught proofing, hanging curtains and blinds and secondary glazing.

How do you make your sash windows more energy efficient?

  • Double Glazing. Installing double glazing on your sash windows can be an expensive option. It will, however, make the room far more cosy as it reduces draughts and improves the appearance and style.

    Sash windows tend to be very old which means modifying them is difficult. To create double glazing, extra window panes needs to be installed just above the existing panes. Some sash windows may not be deep enough to accommodate this so new sashes would need to be made and installed. Ultra thin glass panes are available nowadays that can avoid this problem. They can be fitted with minimal changes to the existing window frame which makes this a good option.

    Switching to a uPVC window will give you all the benefits of a double glazed sash window without some of the usual problems that can occur with a more traditional wooden window. They are considerably cheaper and require less maintenance but would likely lower the value of your property.

  • Draught Proofing. This is one of the most effective ways of improving the efficiency of your windows. As sash windows have panels that slide over each other, they can be more draughty than other styles of windows. Draught proofing them requires creating an air-tight seal around the frame of each sliding window.

    Installing brush strips is a good solution that involves fixing a brush or blade into a carrier and then pinning it to the frame of the window. This method can also be completed yourself if you have a decent level of DIY skills.

  • Curtains and Blinds. This option is great for stopping draughts, particularly in the winter months. If you already have existing curtains or blinds then you may be able to fit a thermal lining to the back of them. If you are adept at DIY, it’s a fairly simple process to put up a curtain rail without the cost of having to bring in a specialist.

    Curtains and blinds can block out some light which means this option won’t be suitable for every room.

  • Secondary Glazing. A number of sash windows are in listed properties so the amount of work you can do to them is limited. Secondary glazing involves installing a second window in front of the first. This has the benefit of providing additional warmth and sound insulation without affecting the original window.

    The first type of secondary glazing is fixed permanent which has panels that slide over each other. This allows you access to the outer window if you wish to open it or it needs cleaning. Temporary secondary glazing involves the extra window frame being attached to the surrounding area using magnets. The whole frame can then be lifted out to get access to the window behind.

    Secondary glazing is a great option if you don’t want to spend a large amount of money or need to retain the original features and looks of your sash windows.

A scheme called Green Deal was started in 2012 by the government to provide financial help to homeowners wanting to improve their properties. Although the government stopped funding the scheme in 2015, you may be able to find a Green Deal provider on the official web page

If you would like to improve the energy efficiency of your sash windows, call the experts at Kelly’s.

Ensuring your sash windows are not causing unnecessary problems like draughts doesn’t need to be difficult. Installing double glazing in your sash windows is just one of a number of different options available to homeowners these days. Our professional team at Kelly’

s can help you decide what is right for your home.

For more information about sash windows, please contact our team on 0800 634 8636 today or you can email us directly at You can also check out our website for more services we offer.


If you would like further information on how we can help to repair, restore or fit any sash windows or doors, please do not hesitate to get in touch with us today. You can call our expert team on 0800 634 863, or alternatively, you can send us an e-mail at