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SPECIALISTS IN BESPOKE SECONDARY GLAZING FOR THE HERITAGE SECTOR

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How original sash windows can be energy efficient

SPECIALISTS IN BESPOKE SECONDARY GLAZING FOR THE HERITAGE SECTOR

How original sash windows can be energy efficient

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Published: 01/10/2025

Sash windows have timeless appeal and can be found on historic and period properties across the UK. Unfortunately, they are not known for their energy-efficiency despite being renowned for their visual appeal.

Most sash windows are single glazed, with many having poor quality sealing around their frames and glazing. Nonetheless, there are steps that you can take to improve energy-efficiency if you are an owner of sash windows.

Let’s explore how…

Draught reduction and elimination
Small repairs to fix cracks and full gaps can eliminate or at least reduce draughts considerably. By adding draught proofing to your sash windows, you can reduce draughts by more than 85%. You can also enhance energy-efficiency by taking steps such as closing roller blinds and thick curtains. There are other steps you can take to minimise heat loss, including using closed shutters to reduce U-values. Of course, these are only cosmetic solutions. If you want to make a substantial long-term difference, then secondary glazing is the best option.

Draught reduction and elimination

How can secondary glazing help?
When you opt for secondary glazing for sash windows, you can add a discreet extra window facing the inside of your building which is not visible from the outside. We have vast experience in providing solutions for sash, casement and York sliders, and we are able to provide glazing in a ‘curved-in-plan’ condition. The secondary glazing solutions that we offer can increase thermal efficiency, eliminate draughts and reduce noise. Each of the units that we supply is individually made and measured for the specific project we are working on.

How can secondary glazing help?

Don’t replace, upgrade
The UK is home to an abundance of historic buildings with sash windows, many of which have or are due to undergo refurbishment and retro-fitting to enhance their energy-efficiency and help the country meet its environmental targets. Owners of sash windows are constantly encouraged to upgrade rather than replace them. A 2009 study by English Heritage showed that even modest repairs could vastly reduce the energy performance of old sash windows and led to many period property owners deciding to have them restored. English Heritage emphasised that it was perfectly possible to restore sash windows to modern energy performance standards without character or aesthetic appeal being compromised. Sash windows can be found on all sorts of buildings, including not only homes but libraries, schools, town halls, museums and more.

Don’t replace, upgrade

Why Storm Windows?
At Storm Windows, we have many years’ experience when it comes to working with the windows of period and listed properties. We are experts in secondary glazing, which can vastly improve the energy efficiency of period windows in a discreet and aesthetically sympathetic way. We are a family-run company that manufactures and installs secondary glazing for listed, classic and historic properties across the UK. Our client network includes a wide range of big names, including the National Trust, National Galleries and more.

Why Storm Windows?

If your looking to bring down your energy-costs and make your rooms warmer and more comfortable, contact us or book a free survey. 

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