Secondary glazing is a fully independent window system, retrofitted on the room side of an external window, improving the thermal, acoustic and security performance of the property. It is extensively used in heritage and commercial buildings as well as domestic homes across Northern Ireland, Belfast and Dublin.
Are you considering replacing your existing windows with new double or triple glazed windows? Consider a secondary glazing window installation instead.
We specialise in providing innovative secondary glazing window solutions tailored to meet your needs, whether you are looking to reduce your business or home heating bills or want to block out unwanted external noise.
Secondary glazing is adding an additional internal window to an existing external window.
This system provides greater thermal insulation, reduces noise intrusion and improves security for your home, business or listed property, without damaging the aesthetics of the original external window. It is an excellent alternative to installing new double or triple glazed windows, as it does not require complete replacement of your existing windows.
Installing secondary glazing adds an extra barrier to prevent heat loss.
Secondary glazing offers a strong defence against intrusive external noise.
Secondary glazing is extremely difficult to open from the outside and provides an additional physical barrier.
Secondary glazing is a discreet window that is installed to the interior side of the room. Available in different styles to suit all window types, secondary glazing will decrease noise levels breaching your primary windows and increase thermal efficiency.
As it doesn’t change the fabric of the building secondary glazing can be installed within Conservation areas and Grade I and Grade II Listed Buildings. We often work with HED for design and specification approval before commencing an install.
Secondary glazing is often installed for noise reduction. Acoustic Secondary Glazing can reduce noise levels by up to 80% (which is the equivalent of 54 dB). Standard double glazing typically offers around 30dB, so the addition of Secondary glazing will enhance noise reduction more than simply adding new double glazing.
Draughty windows can make a room feel uncomfortable and will result in higher energy costs as heat is escaping. Secondary glazing, with either 4mm, 6mm or 8.8mm Low E glass, can reduce heat loss by up to 65% and instantly prevent draughts. We often recommend the installation of Low E glass as it has a specifically designed coating that reflects heat back into the room.
For optimum performance, we recommend that the secondary glazed unit is face fixed to the interior side of your primary window. With an air cavity of no more than 80mm. Secondary glazing will decrease the amount of heat loss when installed with single, double or triple glazed timber or uPVC windows.
We at Secondary Glazing NI advise the installation of a hardwood subframe as this acts as a thermal barrier, preventing the aluminium frame and glass cooling due to the temperature of the fabric of the building.
Please speak with us directly where we can advise which type of glass, product and installation type will yield the best results.
Another benefit of secondary glazing is that it offers an increased level of security. If your primary windows are forced open, secondary glazing acts as a second barrier to unwanted entry. Our windows usually come with a lock which help thwart unwanted guests.
Secondary Glazing NI’s frames are manufactured from durable aluminium and are powder coated which allows them to stand the test of time. Often used in conjunction with single, double, and triple glazed uPVC or timber windows, secondary glazing boasts unique performance that is unmatched by any other window system.
The installation of secondary glazing requires a small air cavity which acts as insulation between your primary windows and the secondary glazing. The air cavity plays a vital role when reducing noise levels or increasing thermal efficiency.
Sound – We advise an air cavity of between 150mm to 200mm. This type of installation is referred to as reveal fix. The secondary glazing unit is installed within the window reveal and can reduce noise levels by up to 80% (54 dB). For optimum performance, we often recommend acoustic glass which is available in thicknesses of 6.4mm, 6.8mm and 8.8mm.
Thermal – To achieve optimum thermal efficiency we recommend an air cavity of up to 80mm. This type of installation is commonly known as face fixing as the secondary glazed unit is fixed to the internal face of your primary window. Specified with a Low E glass correctly installed secondary glazing can reduce heat loss by up to 65%.
Our secondary glazing is available in many styles, complimenting all window types. We have a range of windows that slide horizontally and vertically for easy access and cleaning.
Our hinged unit operates on a hinged mechanism that can be placed on the side of the window for conventional opening, or on the top or bottom dependent upon your requirements. Other window styles include fixed windows or lift outs which can easily be lifted out of the frame.
We will work with you to offer a range of products that are discreet, functional and high performing. Our product range is suitable for all types of windows and can be tailored to meet most budgets.
Secondary Glazing NI’s units are manufactured to order in bespoke sizes and colours. We can bend/arch frames in house to suit any window size, shape or style.
As our products are made to order, we can manufacture units that match both transoms and mullions to reduce sightlines and make the secondary glazing even more discreet. For larger windows, typically commercial applications, we can stack or couple single units to achieve the required coverage.
Our products are manufactured from durable aluminium and our most popular colour is Standard White with a high gloss finish. In addition to standard white, we can offer stock colours which include:
Van Dyke Brown (BS08B29, Gloss)
Cream (RAL9001, Satin)
Grey (RAL7016, Satin)
Ivory (RAL1015, Satin)
Black (RAL9005, Satin)
Traffic White (RAL9016, Matt)
Pure White (RAL9010, Satin)
If you are looking for a colour that is more bespoke, we can also offer 200 additional RAL colours to suit all taste and preferences.
Secondary glazing is normally specified to combat 2 main issues: acoustic or thermal performance. In conjunction with the air cavity, the type of glass specified plays a vital role in rectifying your issue. As standard, all of our products are manufactured with 4mm toughened glass for enhanced security and safety.
Secondary Glazing NI also provide several types of options offering enhanced heat and / or acoustic properties.
Sound – Selecting the correct glass and installing the secondary glazed unit with an air cavity of 150mm to 200mm, can drastically reduce noise issues by up to 80% (54 dB). Most traffic noise problems can be rectified with the installation of either 6.4mm or 6.8mm clear acoustic glass.
Where noise is a real nuisance, and loud in nature, we suggest the specification of 8.8mm clear acoustic glass.
Thermal – Cold draughts breaching your primary windows can make a room feel uncomfortable and makes it uneconomical as the loss of heat will result in higher energy costs. Where thermal performance is required, we advise the installation of either 4mm, 6mm, 6.4mm or 8.8mmlaminate low E glass. Low E glass has a specifically designed coating that reflects heat waves back into the room thus keeping your it warm in the winter, and cool in the summer.
We will discuss the options with you specific to your requirements, however we commonly install 6.4mm laminate which offers great acoustic and heat properties, as well as being a safety glass suitable for many installations.
Secondary glazing can offer value for money by improving the energy efficiency of windows without the need for complete window replacement. It is a cost-effective solution that can lead to significant savings on energy bills over time. The installation process is quicker and easier than replacing windows, and it can be a more sustainable choice, especially for homes in conservation areas or those with listed buildings. While the initial cost may be similar to double glazing, the long-term benefits in energy savings and comfort can make it a worthwhile investment. This is especially tied into the improvements of secondary glazing for noise and heat improvements compared to traditional PVC double glazed windows.
Over its lifetime our secondary glazing will pay for itself whilst giving you warmer, quieter, safer and draft free rooms.
*This is based on standard double glazing at 2.7 U Value, and Timber at 4.7 U value over an area of 3.75m2*
We recently fitted our Acoustic Secondary Glazing into this beautiful period home in County Down. The owner wanted improved heat retention, a quieter home and
We recently installed our acoustic secondary glazing in this noisy bedroom in county Down. The bedroom overlooks a busy road and the owner wanted a
At Secondary Glazing NI we provide and install aluminium sliding hatches for office reception areas, in the home, restaurants, café serveries or other commercial settings.
Looking for trusted secondary glazing installers in Northern Ireland, Belfast or Dublin? Our expert team is here to help you choose the perfect secondary glazing windows for your home or business. Whether you want to improve insulation, reduce external noise or add an extra layer of security, we provide tailored solutions that are cost effective and hassle free.
Get in touch today for a free, no obligation quotation.
Email: sales@secondaryglazingni.com
Our team has more than 25 years of experience working with homeowners, landlords and businesses, providing professional installations of secondary glazing systems, including vertical sliders, hinged units and sliding windows.
If you are considering replacing your existing double or triple glazed windows, speak to us first about the benefits of secondary glazing installation.
