Cardiff's Premier Double Glazing Installer - Windows, Doors, Conservatories and Roofs

green granada secondary glazing

Secondary Glazing

Secondary Glazing is the perfect complement to your existing single glazed windows. Superb weather and soundproofing for homeowners who cannot replace the primary windows.

Energy Efficiency and Security

When you need better insulation, sound reduction and security but cannot change your existing single glazed windows, Secondary Glazing may be the perfect solution for you.

Read on to discover how Heath Windows and Doors Cardiff can help you live more comfortably and reduce energy bills with stylish secondary double glazing you will love.

What is Secondary Glazing?

Secondary glazing is a windows system that is fitted inside your existing windows. Our secondary glazing is unobtrusive and robust and blends seamlessly into your home.

Our aluminium secondary glazing units offer the perfect solution to protect your existing windows from drafts and noise. Installing discrete, slim aluminium secondary glazing instantly improves acoustic performance while adding an extra layer of security on the inside.

Fly Screens

Secondary glazing doesn’t have to be glazed. Instead of glass, your frames can be fitted with mesh fly screens so you can leave your windows open all summer without those pesky flies buzzing around. This is also useful if you are scared to open windows in case a child or pet tries to climb out of them.

If you are thinking of installing secondary glazing, get in touch. We are happy to explore the options with you and give you an idea of the price.

wooden granada secondary glazing
rectangular granada secondary glazing over arched windows

Designed Around Your Existing Windows

Cheap secondary glazing is often simply two sliding windows. This means the frame doesn’t align with your existing frames, creating an ugly view. Our secondary glazing system is flexible, allowing for a wide range of styles. 

We will design your secondary windows to integrate perfectly with your existing frames. We will match the existing frames so that they are virtually undetectable from the outside view.

Whether your current windows are sash windows, casement windows or tilt and turn, secondary glazing will still work for you, and you will still be able to open the windows and access them for cleaning. This is because we will design them to match frame to frame.

Secondary glazing installation can be completed quickly with minimal disruption to you or your home in just one day.

Enjoy the Energy Efficiency of Double Glazing When you Can’t Replace Your Windows

Secondary glazing improves energy efficiency, weatherproofing and draught exclusion by providing a sealed physical barrier inside the existing window. An overall U-value of 1.5 W/m2K can be achieved by installing our secondary glazing.

The energy efficiency of your existing windows will play a part in the overall performance. The current U-value is the starting point, and whatever it is, secondary glazing will improve it.

We will always design your secondary glazing so that it is in line with your existing windows. Not only does it look better to do that, but we also want to make sure you still have access to your windows for opening and cleaning.

granada secondary glazing over leaded windows
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More Than Just Double Glazed Windows

A low U-Value means you will have an easier time keeping your house at the right temperature. A well-insulated building is also less expensive to heat and maintain due to lower energy bills. This reduces CO2 emissions as well. It’s good for both your bank balance and our environment.

At the moment, you probably have solutions such as closing blinds or curtains and taping plastic across the windows. You already know that those solutions offer benefits, so imagine how it will feel with purpose-built secondary glazing that looks fabulous, is easy to use and doesn’t have gaps for the cold air to escape from.

Noise Reduction of Secondary Glazing

You’ve probably become so used to it that you are unaware of the continuous noise from traffic, mowing lawns and even trains if you live close to a railway. You’ll be amazed at how much calmer your home feels with less background noise.

The optimum noise protection in secondary glazing comes from installing with 100-150mm gap between the primary window and secondary glazing with 6.8mm acoustic glass. This combination could give you a reduction of 20db.

If you live in a particularly noisy area, you may benefit from secondary glazing even if you have modern windows. Flight paths and areas near train lines or schools can cause stress because of persistent noise. This is one instance when it may be worth paying more for extra insulation on top of that already offered from your double glazing.

Secondary glazing can improve sound insulation by approximately 85% and may be cost effective compared to replacement with triple glazed windows.

granada secondary glazing over ggeorgian windows
full wall granada secondary glazing

When You Can Choose Between New Windows and Secondary Glazing

If you are considering secondary glazing because it’s a cheaper option than full double glazing, then we can’t categorically state that secondary glazing is better. It depends on what is there now.

If you have double glazing that is old but still reasonably effective, the addition of secondary glazing could possibly give you a combination that is more energy-efficient than double glazing alone. In effect, you are creating a triple-glazed system of sorts. However, if your old windows are single-glazed, the combination may not be as effective as new double glazing.

Our advice and quotes are free, so the best thing is to book an appointment for a home visit.

When Secondary Glazing is the Only Option

If you have the option of replacing your windows with new double glazing or triple glazing, then overall that is a better solution.

Secondary Glazing is a solution for people who need better performance from windows that are not doing an effective job on their own.

Reasons to use secondary glazing include; restrictions because of historic building regulations, conservation area restrictions and cost.

The first two leave no other option. You cannot change your windows; therefore, secondary glazing will give you similar benefits to double glazing.

granada secondary glazing in bedroom
llandegveth secondary glazing (2)

Protect the Character of Existing Primary Windows with Smart Secondary Glazing Solutions

Our customers in this listed building in Llandegveth were absolutely thrilled with this bespoke installation. The integrity of the existing primary windows is maintained, but the client now benefits from improved sound reduction and thermal insulation.

The units are unobtrusive and are easily removed for cleaning.

We have installed made to measure secondary glazing in many listed buildings and every client has been delighted with the extra protection. 

Is Secondary Glazing Strong?

Secondary Glazing Designed to Last.

Our secondary glazing units create a robust internal window system designed to last. If you are considering secondary glazing as a temporary measure because you may consider changing the windows in the next couple of years, we urge you to find a way to fully replace the windows. This would be cheaper than paying for a temporary solution now with the additional cost of replacing windows within a short time.

We are happy to take the time to consider your options with you. Call us on 02920 650 854 to book an appointment or pop into our Cardiff showroom.

How Much Does Secondary Glazing Cost?

The cost of installing secondary glazing depends on the size and shape of your windows, how they open, how many windows you need and the type of material you choose.

Our secondary glazing comes fully glazed with 4mm toughened safety glass as standard. For larger units and premium results, upgrading to 6mm glass is recommended. Specialist glass options are also possible. These include acoustic or security laminated, tinted for privacy and some decorative options.

We don’t charge for quotes and there is no obligation so feel free to call us to arrange for us to measure. You can also bring rough measurements into the showroom if you prefer.

How is Secondary Glazing Installed?

Most houses have windows with window sills and reveals that secondary glazing can fit into. Older buildings may have windows that are flush with the wall, so the secondary glazing will need to be face fixed. This can be done by fixing directly to the wall or with a timber subframe.

Reveal Fixing

This is the most popular and effective way of adding an acoustic window to your home. A 100-150mm cavity between the primary window and secondary glazing ensures increased acoustic performance while also reducing sound transmission.

Secondary frames are installed by fixing sideways through the aluminium (and timber) sub-frame, directly into the walls of the window reveal. The reveal is the recessed area that your window sits in.

Face Fixing

Your secondary glazing will need to be face fixed if there is no reveal to fit into. This may also be suitable in older buildings where the window reveal is not square. We’ll assess your windows for the best way to fix them depending on the surface and whether architraves are in place.

If the glazing stands proud of the wall, you may consider framing it with an architrave. We will also assess to ensure any handles or other protrusions will not be in the way. This is one reason we may consider a timber subframe to create extra depth.

Secondary glazing on sash windows with horizontal sliders reduce noise and heating bills in a listed building.

Timber Subframe

Timber subframes are a great way to give doors and windows an even, attractive appearance. If we find that the reveal fixing is uneven or out of plumb in your frame, then adding timber can fix this issue. Timber helps shape these small adjustments, so they fit snugly. Not only does it create beauty for our aesthetically-minded customers but also provides strength as well when used properly to reinforce stress points on frames during installation. We use specially moulded hardwood subframes to integrate with the aluminium frames.

Is Finance Available for Secondary Glazing?

Our complete range of products is available on finance, including conservatory roof replacement, windows and doors and conservatories.

If you are considering new secondary glazing, contact us to first arrange for us to visit, measure up and provide a quotation.

Before making a decision about new windows, consider your budget and all of the available options carefully, as this will help you to settle on a solution that provides maximum enjoyment.

Is Secondary Glazing Available for Shaped Windows?

If you think your needs are too complex, think again. We supply even the most difficult of shapes. We can construct any size, shape and style of secondary glazing. With our wide variety of shapes, such as arches, circles, rakes and angles, we haven't come across a shape we can't make. Some shapes are not suitable for hinges and these are made to lift out. Frames and styles can be combined to ensure the right fit while being manufactured with exacting precision for perfect finishing touches.

If you are considering secondary glazing just so that you can keep the stained glass, you may be able to encapsulate your old window. Find out more about stained glass windows.

Stained glass windows protected by secondary glazing

Which Buildings are Suitable for Secondary Glazing?

Secondary glazing can be used in any type of building. Modern homes in busy areas, old buildings with draughty windows. Offices, hotels, churches and schools. All of these have had secondary glazing.

The question to be asked is; do you need better weatherproofing, security and sound insulation than your current windows provide? If so, then secondary glazing may be the answer.

Buildings in Conservation Areas.

Replacement windows may be prohibited in some conservation areas or on buildings of historical significance.

In most cases, secondary glazing does not change the outward appearance and is, therefore, allowed.

In some conservation areas, the new uPVC flush windows are being permitted, so if you haven’t checked for a while, it may be worth asking if rules have been relaxed now that flush windows offer such a good alternative to timber windows.

If you are unsure whether there are restrictions on your property, the answer can usually be found in the deeds to your house. The local planning permission department is also usually helpful.

Can you get Secondary Glazing for Doors?

Secondary glazing isn’t just for windows. You can also install it for patio doors. We often find our customers in Cardiff have replaced the windows but still have the old doors. There are no rules to say they all have to be done together, and as you would expect, new patio doors are not cheap. Secondary glazing may be the answer. Like the window systems, they can be reveal or face fixed and offer all the same benefits.



Bifold Doors


Secondary Glazing Cardiff – Secondary Glazing Newport


Old windows tend to be vulnerable if you’re unlucky enough to be targeted by a burglar. Secondary glazing adds another layer of security with the addition of more glass that cannot be opened if they penetrate the primary windows. Secondary glazing can be locked from the inside to improve security. The presence of the secondary glazing sends a visible signal that you will not be an easy target.

There are many benefits to secondary glazing units, including reduced heat loss, sound insulation and improved security without compromising the external character. 

Quotes are always free and without obligation,

granada secondary glazing on crittal windows

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