Secondary Glazing Buyers Guide Blog Image

With energy costs soaring and cold weather patterns increasing, it is essential homeowners act now to reduce their heating and electricity bills. Families across the UK are now choosing between eating and heating. There’s no secret that keeping our houses warm is expensive. It was reported that the average cost to heat a UK home is now between £400-£500 a month, which is almost 10% of income on heating bills alone. It’s now estimated that the average household in the UK spends nearly a third of all their disposable income. Disposable income is after the tax man has had his share so now is the time to act to reduce your energy bills.

We have one of the best ways you can reduce your energy bill by up to 10%: secondary glazing. With benefits such as a warmer home, noise reduction, extra security, and easy installation there is no reason why UK homeowners should not be doing this today!

Read on to find out how you can benefit from a low-cost and DIY secondary glazing project to bring down your energy costs this winter.

What is secondary glazing?

Despite the answer in the name, this is a common question we get asked a lot: what is Secondary Glazing? Well, it’s very simple, Secondary glazing is a glazing system where a secondary window layer is installed over the top of your existing window.

It is beneficial to have Secondary Glazing kits installed as adding a glazing sheet layer over your original window will increase heat retention. And that’s not the only benefit.

It is a fantastic option especially compared to the alternative of having to replace your windows, which is going to be very costly. A large expense that a lot of people can’t afford.

What does secondary glazing do?

Secondary Glazing adds another layer onto your existing window to create a small insulating gap, which acts as an insulation barrier, preventing heat and sound from passing through, while preventing cold air from entering your home, allowing your home to become more energy efficient.

Sekosnap Secondary Glazing systems work with a similar method to double glazing but without the large costs, as we will learn in a while.

Benefits of Sekosnap Secondary Glazing Graphic

The extra insulation gap reduces the amount of heat transfer from inside to outside. Gaps in your windows will cause you to pay more on your energy bills than necessary due to heat leakage. It will reduce the amount of warmth you have coming from your heating system. 

How effective is secondary glazing?

All properties lose heat through their windows and doors to some degree. Older properties are particularly prone to a high level of cold draughts, especially if they have single glazing or old double glazing. Secondary glazing is an effective method of reducing heat loss as it creates a small gap that acts as an insulating barrier.

Although secondary glazing is not as effective as installing new double-glazing windows there is still a significant money saving for a lot lower cost. Secondary glazing can save you up to 10% on your energy bills depending on what windows you currently have installed.

As well as saving on your heat loss and energy bills, another huge benefit is that installing it can reduce noise and air draughts. If your warm air is escaping through your windows, then that means cold air will also be coming in which can make a room feel breezy. The additional layer of a secondary glazing kit will help eliminate these draughts. What’s more, having another layer will also reduce any noise pollution from outside and make your whole room quieter.

To learn more read our blog about how secondary glazing works.

Secondary Glazing Cost

We now know how effective secondary glazing is but how much does secondary glazing cost? The first thing to calculate is how many windows you have on your property and the size of these windows. Naturally, the more windows you have the more glazing sheets and secondary glazing you will require.

The cost of secondary glazing is very cost-economical, from only £40 per square metre.

It is worth noting this does depend on the thickness of the secondary glazing sheet you have chosen.

Although there will be an initial cost to install secondary glazing, it will quickly provide you with an excellent return on your investment with a reduction in your energy bills. As you do not need to hire a tradesman to install DIY secondary glazing is a low cost solution to employ.

Is secondary glazing cheaper than double glazing?

Yes, secondary glazing kits are substantially cheaper than double glazing.  In fact, on average secondary glazing is 15 times cheaper than double glazing, making this a perfect solution that will benefit your bank account in more than one way.

Secondary glazing is cheaper than even PVC windows. It might surprise you to know on average secondary glazing is a quarter of the cost of the most basic PVC window. Basic white UPVC windows are on average £240 to £1,800 per window to buy, depending on your window size and style, such as casement sash, tilt and turn or bay. Plus the cost of hiring a window installer which can range from £100 to £400 per frame. On top of this, there may also be additional unexpected costs such as the removal and disposal of your old windows.

If you are considering replacing sash or old heritage windows then secondary glazing is going to save you a lot. Sash and heritage windows are expensive even for repairs never mind having to replace them. When you include the extras such as frames and labour it can all add up quickly!

Unlike double glazing, secondary glazing can also be installed by DIYers. Double glazing involves having to hire professionals for installation, which does not come cheap. For an average home of 8 windows and 2 UPVC doors, you’re looking at between £6,000 and £15,000 just to install. It is also important to remember additional costs you may not have factored in such as scaffolding, plasterers, and painters once the new windows have been installed.  Secondary glazing is the way forward for saving on installation costs.

Choosing Secondary Glazing

What is the best type of secondary glazing?

Over the years, Secondary glazing has improved and advanced. Traditional secondary glazing was made from wood, however, this brought longevity issues. Timber can rot with moisture and warp over time, causing gaps which could leak water and air. This can defeat the purpose of secondary glazing which requires a strong seal.

Modern secondary glazing systems are made from aluminium. An aluminium system is the best type of secondary glazing due to its strength, longevity and recyclability.

Magnetic secondary glazing is another lightweight, and quick-to-install option but can decouple too easily. It is not the most dependable choice when choosing secondary glazing. Magnetic secondary glazing also does not work the same as traditional secondary glazing. As it is a magnetic strip that is easily removable it does not have the tightest seal, which means it’s less effective at reducing noise and preventing draughts.

What thickness of the Glazing Sheet for secondary glazing?

With a variety of thicknesses available in Axgard Secondary Glazing Sheets, there are multiple options depending on your budget. A 3mm polycarbonate sheet is the best sheet to use for secondary glazing.

Axgard shatterproof glazing sheets review image

A 3mm sheet is very rigid and has a high-impact strength. If you are on a tight budget, then 2mm can be used however you should be aware it will not be as rigid so for the best results the thicker the better.

Do I need planning permission for secondary glazing?

So, you have decided Secondary Glazing is the way forward and you wish to have it installed, but do you need planning permission? Before starting any home renovations, it is always worth double-checking. Generally, if installed on the interior of your home then permission should not be required. As the original window remains in position and unaltered then you are good to go ahead so even a basic DIYer can complete secondary glazing.

However, if you have a listed building, live in a conversation area, or have specialist sash windows then planning permission could be required. The best thing to do would be to always check with your local area first. Information can be found on your local council website and who to contact if in any doubt.

It is also worth mentioning that secondary glazing can be removed at any time after installation. This option means it’s a non-permanent solution for lowering your energy bills. It also means you can save yourself the hassle of applying to your local council.

CONCLUSION: is secondary glazing worth it?

With many families across the UK facing large energy bill increases, secondary glazing is well worth considering as a simple solution that will make your home more energy efficient.

If you would like to save up to 10% off your energy bills, then the way forward would be to install Secondary Glazing. It is cheaper than double glazing and you do not require planning permission so is a straightforward project.

Secondary Glazing has good benefits to offer such as reducing the amount of heat escaping out your windows and with no professional installer required this can be done by any DIY homeowner.

When you choose to install Secondary Glazing on your home it is important to install the process: watch our how to install secondary glazing video and read the related blog to learn more.

Need Help with your Secondary Glazing Project?

Please contact us if you have any further questions regarding Sekosnap® secondary glazing. Our Live Chat Teams are always happy to discuss any questions with you. Alternatively, you can email where our Teams will provide you with all the advice and support you require for your projects.

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Clear Amber Shop Team

Clear Amber Shop Team

Thanks Robert. For expansion you should allow a couple of mm either side of your glazing sheets. Axgard Sheeting is very easy to trim down so a lot of installers tend to trim on site. Simply follow our How2cut Axgard video. This is worth considering if your windows or doors are older and potentially not square.

Robert Bunney

Robert Bunney

I presume you should order Perspex sheet cut to a slightly smaller size to allow expansion/contraction. I am using the Sekosnap over 2 glass panels in a front door. Measured sizes to the floor of the 15mm recess in the Sekosnap are 800mm x 600mm and 700mm x 1000mm. What size do you recommend I should order of 3mm thick perspex?



Thank you for the informative guide on secondary glazing This is a valuable resource for anyone looking to improve energy efficiency and reduce noise in their home. A step-by-step approach is especially helpful.

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