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Discover the benefits of secondary glazing windows. This detailed guide gives you all the information to help you decide if secondary glazing is right for you.
Secondary-glazing windows are a great alternative to double glazing. It’s possible to DIY or use an installer for this process. It doesn’t involve completely replacing the windows but rather adding a pane of glass to existing single glazed windows, so it tends to be a much cheaper option than installing double-glazing windows and a great one for those who are unable to replace single glazing. Our guide will take you through what secondary glazing is, how much it could cost you and who it’s best for.
Secondary glazing essentially involves adding a single glazed pane of glass or plastic to the frame of an existing single glazed window. It’s an effective way to keep heat in and save on energy bills and is a cheaper and easier way to upgrade single glazed windows than to completely replace them with double glazing ones.
The panel is installed on the interior of the existing window, creating an extra layer of insulation and security. As it’s fitted onto the inside of the window, the panel won’t be visible from the outside, but it’ll make the windows harder to break and will also reduce noise.
Upgrading from single to double glazing on listed or historic buildings or houses in conservation areas might not be allowed, and that’s where secondary glazing can come in – you won’t need to completely replace the windows, and it’s a temporary measure that’s easy to do yourself.
Historically special houses, such as this one, might be prohibited from replacing draughty single glazed windows with new double glazed units. Secondary glazing allows homeowners to increase efficiency in their older properties.
Some research suggests that secondary glazing can reduce outside noise more than double glazing, providing noise reduction of up to 54dB. It’s ideal for those who live on very busy roads and wish to have a bit more peace and quiet.
An extra pane of glass or plastic, usually of a different thickness to the glass already in your window, provides an extra layer of security. This will make the windows harder to break into.
One of the biggest pros of secondary glazing is that it’s a DIY option (though you can hire an installer if you wish), and it’s much cheaper than installing double-glazing windows.
| Type of glazing | Cost | Energy efficiency | Noise reduction |
|---|---|---|---|
| Secondary glazing | Around £100-£500 per window | Reduces heat loss by 60% | Up to 54dB |
| Double glazing | Around £250-£3,600 per window | Reduces heat loss by up to 83% | Up to 31dB |
There are several different types of secondary glazing windows, including:
Hinges can either sit on the sides or at the top and bottom of this type of window, which opens like a casement window.
Vertical sliding secondary glazing is designed for sash windows, as it allows the new pane to move in the same way as the original sash window.
In contrast to vertical sliding glazing, horizontal sliding secondary glazing is best suited to wide windows, and it’ll allow the pane to slide or move horizontally rather than vertically.
This type of secondary glazing is less permanent than vertical or horizontal glazing and uses a pane that can easily be removed (or lifted out) from its frame.
With the magnetic option, your secondary pane of glass will be attached to the inside of your window with magnetic strips. If you choose to DIY your secondary glazing, it’ll likely be with this type of fitting, as it’s an easy, cheap and flexible option.
The cost of secondary glazing will depend on what type of windows you have and whether you opt to install them yourself or have an installer do it for you. The average cost of secondary glazing for one window, including the labour cost of installation, is around £300, but you could pay up to £550.
One of the benefits of secondary glazing is that it is an affordable alternative to potentially high double glazing costs.
We’ve set out the average costs of secondary glazing for each type of window:
| Type of window | Cost per window |
|---|---|
| Hinged secondary glazing | £350-£550 |
| Vertical sliding secondary glazing | £350-£500 |
| Horizontal sliding secondary glazing | £350-£500 |
| Lift-out secondary glazing | £300 |
| Magnetic secondary glazing | £100-£200 |
Triple glazing windows will cost significantly more than secondary glazing, but it’s generally believed to be much more effective and energy efficient. Triple glazing is around 30% more effective for sound insulation than double glazing, which offers around 42% noise reduction. However, secondary glazing is thought to be one of the most effective ways to keep sound out, reducing up to 70% of noise.
When it comes to energy efficiency and heat loss through windows, switching from double to triple glazing could reduce heating expenses by 10-15% per year, while switching from single glazing to double glazing could save you around 10% per year. That said, secondary glazing isn’t always thought of as a long-term solution; triple glazing will cost you more, but it’ll be an investment that pays for itself in the long term.
Essentially, triple glazing will give you the best results for a long-term investment if you’re willing to spend the money. But secondary glazing is a great alternative for people who live in listed properties and can’t upgrade to triple (or double) glazing and those who want to reduce energy consumption and noise levels more cheaply and easily.
Considering secondary glazing is significantly cheaper than double and triple glazing and can give homeowners with single glazing many great benefits, we think it’s definitely worth the cost. It’s also a more temporary measure than double or triple glazing, as the panels added to the windows can usually be removed. And because the cost is low, you won’t feel like you’ve wasted money on a temporary solution.
If you’re looking for secondary glazing companies, some of the best double glazing companies will also provide this service. Two of the most well-known window installation companies, Anglian and Everest, offer a range of secondary glazing options for different types of windows, which will cost you less than double or triple glazing installations. Be sure to approach a few different companies for a quote before making a decision.
