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Can’t replace your windows? Try secondary glazing

Friday, 3rd February 2017

A case study shows that where installing new energy efficient windows is not an option, secondary glazing can provide many of the same benefits

Installing energy efficient glazing can help make your home warmer, quieter and more comfortable to live in – and help lower your heating bills.

However replacing your old windows may not always be an option. Whether your budget doesn’t stretch that far or it is impractical or impossible (due to planning restrictions) to replace your current glazing, that doesn’t mean you can’t take action to reduce the heat lost through your windows and enjoy all the resulting benefits. has drawn a case study from GGF Member company Selectaglaze to show how you can overcome the problem when you can’t replace your existing windows or doors.

Case study: Brighton’s historic Ship St Post Office

One reason window replacement may not be an option is when the property in question is a Listed or Historic building.

That was the case with Brighton’s historic Ship St Post Office building, the city’s main post office for many years. Dating back to 1925, and incorporating parts of an earlier building dated 1898, it was recently renovated with the aim of transforming it into comfortable apartments.

However creating warm living spaces turned out to be quite a challenge. The primary windows were draughty, allowing heat to escape and due to the listed nature of the building they could not be changed.

For many homeowners living in heritage or listed properties this can be the reality. Luckily it needn’t be a deterrent.

Secondary glazing solution

In this case, secondary glazing provided the ideal solution. A separate window fitted inside the existing primary window, it traps an insulating layer of air which can reduce heat loss by up to 50%.

Secondary glazing is fitted to the room side of the building and is fully reversible, making it a popular choice for heritage properties.

As well as improving the thermal efficiency of windows, secondary glazing can help reduce the amount of noise that enters a property through closed windows.

GGF Member company Selectaglaze installed 75 vertical sliding units at the Ship St address. All units are bespoke to ensure the tightest fit with matching sight lines where possible, to make them virtually unnoticeable from the outside.

More about secondary glazing

An introduction to secondary glazing and its benefits: What is secondary glazing?

Be inspired for your home: View our secondary glazing gallery

Related topics

– How double or triple glazing helps reduce window condensation
– How to design an energy efficient conservatory
– Glazing and noise reduction in homes
– Low emissivity (Low-e) glass and thermal efficiency
Advice on ventilation when replacing windows


bedroom with bed and windows

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