What is Secondary Glazing?

What is Secondary Glazing?

Most people have heard of single and double glazing. They’re aware of the pros and cons of both options and know that most people recommend double glazing for their property’s windows. But are these the only options when it comes to your windows?

What if window replacement isn’t a practical option? Or you already have double glazing and it isn’t enough? Maybe you just want a more effective solution? That’s where secondary glazing comes in.

What is secondary glazing? In short, it’s a high-performing alternative to double glazing that could reduce noise, improve insulation and boost security without impacting the style of your home. This post will cover all things secondary glazing: its uses, benefits and even how you could install it yourself.

What is secondary glazing? – The basics

Secondary glazing essentially means installing a ‘secondary’ pane of glass as a fully independent window, with a gap of air in between itself and the existing window pane.

The secondary window is a completely separate unit, consisting of a single glazed pane within its own frame. It’s typically fitted on the interior side of the existing windows before being sealed around the edges.

As opposed to double or triple-glazing, which involves removing the existing window and replacing it with a new one, secondary glazing installation keeps your existing windows in place and simply adds an extra pane.

The additional window pane transforms inefficient single or double-glazed windows into high-performing units, providing the benefits of modern double-glazing without the time and cost of installation. However, because the gap between the panes is bigger, it could even provide more efficiency than alternatives like expensive double glazing.

What are the benefits of secondary glazing?

Secondary glazing offers a variety of benefits for homeowners and property maintenance companies…

Thermal insulation

Energy costs are constantly rising and heating bills can be extortionate, especially in the colder months. Without proper insulation from your windows, you could be losing up to 35% of your home’s heat through your windows and walls.

Using secondary glazing, you can improve your windows’ thermal performance by over 60%. In fact, installing secondary glazing could significantly increase the efficiency of your home and reduce your energy bills by around 10-15%.

Sound insulation

Traffic, street and even aircraft noise can be detrimental to your living environment and your quality of life. The problem is amplified for those living in period properties with original single glazing and poor sound insulation, as they can’t replace their windows.

Secondary glazing is one of the most effective solutions for preventing noise intrusion through your windows. Extra panes of glass are added to the inside of existing windows, with the air gap acting as a barrier to increase sound insulation. You can even increase the gap between the two panes of glass to improve the sound insulation properties.

Condensation elimination

The air in your home is full of moisture from cooking, showering and even boiling the kettle. If your windows aren’t efficient, this moisture will be drawn to their cold interior surface. This is a common issue for single-glazed windows – but can also impact on poor quality double-glazing.

Moisture can get inside gaps in the unit, causing condensation to build up between the two panes of glass. In either case, condensation can ruin the appearance of your home, leaving your windows looking misty – not to mention the issue of wet windowsills when condensation rolls off the glass.

Secondary glazing creates an effective internal seal that stops moisture getting through. It also stops the interior pane of glass getting too cold, which prevents condensation forming.

Increased security

Single glazing windows are easily broken, whether it’s by a mis-hit football or even a potential thief. Doors and windows are the most obvious and easiest way to break into a building. Fortunately, a secondary glazing panel offers a discreet, extra layer of protection to prevent break-ins.

Secondary glazing can also be installed in any home or building. So, whether your property is listed, situated in a busy urban area or you just have an abundance of windows, you can rest assured that your home is better protected and more secure with secondary glazing.

Environmentally friendly

Secondary glazing is a more environmentally-friendly solution than window replacement. Double glazing involves a much more complex process to remove the window, produce entirely new windows and install the double-glazed windows.

The majority of double-glazed windows are made using uPVC casings and fittings too. The manufacturing of this material is highly energy-intensive, using toxic chemicals which can result in health hazards during production. On top of all that, the disposal of old uPVC windows can be hugely damaging to the environment.

In contrast, secondary glazing doesn’t involve costly and damaging production processes as you are simply adding another pane of glass to your existing window. You don’t need to remove anything from your home, dispose of any glass or fittings or waste excess energy transporting the panes.

Easy installation

Secondary glazing window panes are so easy to install, you can do it yourself. Even better, because they don’t damage your existing windows, they can be used in all properties. That’s particularly beneficial in period properties or listed buildings, where it’s not advisable – or even prohibited – to replace windows.

Fortunately, secondary glazing provides all the benefits of double glazing – with a few extras on top – without the invasive installation process. You don’t need to apply for planning permission, even in a protected building, to make these simple, quick and easily reversible changes that can make a huge difference in your home.

Who are we?

At Clearview, we have been designing and producing high quality secondary glazing solutions for over 20 years. Our professional team design, survey and install secondary glazing for a variety of buildings across the UK.

Whether it’s our expert secondary glazing installation or high quality DIY secondary glazing kits, you can reduce noise, improve insulation and increase security inside your property with Clearview.

Discover How To Stop Draughts for Good And Save On Your Energy Bills

This free eGuide – written by specialists – explains in simple terms how to improve the thermal efficiency of your windows by more than 60% and how you can reduce your yearly heating bill by 15%.

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Clearview secondary glazing - the solution to significantly improved acoustic and heat insulation to your property, making your home or offices more comfortable, secure, greener and cost efficient to run. Achieved without the disruption of replacement windows, and without damaging the character of your building.

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