Secondary glazing is regularly confused with double glazing, but they are actually two distinct products.
Secondary glazing involves installing an additional window behind the existing window.
Double glazing involves installing a single window comprising two panes of glass, often separated by argon or krypton gas which forms an insulating barrier.
Is secondary glazing as good as double glazing?
Both secondary glazing and double glazing can considerably improve energy efficiency and reduce your heating bills. So, which one is better?
Double glazing can be up to twice as effective at stopping heat from escaping your property. However, planning permission is often required to install double glazing and if you own a listed building double glazing is unlikely to be approved.
In contrast, secondary glazing doesn’t require planning permission and is often recommended by planners as a good way to improve energy efficiency in a listed building.
Secondary glazing has been shown to offer better acoustic insulation than double glazing.
The larger the gap between the panes of glass, the better the acoustic insulation will generally be, as this gap helps cut out the noise coming through the windows and into the property.
Therefore, unless you choose a specially designed acoustic glass in your double glazed windows, secondary glazing will normally perform better for noise reduction.
So which should I choose?
The answer to this will depend upon what benefits you are looking to have and whether you live in a listed property.
At The Sash Window Workshop we have over 25 years’ experience installing both secondary glazing and double glazed windows into period properties.
Our sales surveyor will be happy to help talk you through the different options available to you, including the different glass options, to help identify the best option for your home.