Acoustic Glass: Noise Reduction Windows

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Discover a world of peace and quiet even amidst the busiest of streets. Thanks to the advent of cutting-edge advancements such as acoustic glass and heritage double-glazed, those residing in bustling areas no longer need to endure constant loud noises.

These innovative solutions can be seamlessly installed into existing frames of traditional sash windows, allowing you to create a serene environment within your home.

Whether it’s the noise from planes, cars, trains, or loud individuals on the street, unwanted external sounds can be a real bother when you’re trying to sleep, work, or simply relax indoors. This article outlines the fundamental aspects of acoustic glass and provides alternative solutions to help restore a tranquil atmosphere to your living environment.

What is Acoustic Glass?

Acoustic glass is typically composed of a pair of laminated glass panes, joined together by an internal layer specifically engineered to absorb sound waves and vibrations. This intelligent design minimizes the transmission of noise through the window, creating an environment of tranquillity within the enclosed space.

Average high-street car noise pollution is around 70 dB

For enhanced acoustic performance, additional layers of glass and internal bonding can be incorporated, further fortifying the barrier against sound intrusion. When combined with a meticulously crafted frame featuring top-notch seals to prevent sound leakage, the efficacy of acoustic glass in impeding noise transmission is significantly heightened.

The benefits of Acoustic Glass- Noise Reduction

Experience the multitude of benefits offered by Acoustic glass, with noise reduction taking centre stage. By mitigating noise pollution, Acoustic glass creates an environment of tranquillity within residential spaces, ensuring a pleasant and restful living experience.

Sash Window Refurb retrofits Slim-profile double-glazed units to original timber sashes that can reduce noise by 36 dB

It is essential not to overlook the dangerous effects of loud noise on one’s well-being. From elevated blood pressure and heart disease to sleep disturbances and stress, unwanted noise can pose significant health risks. Worryingly, the consequences on children are especially troubling, as it has been known to obstruct memory, distractibility, and reading competency.

While noise reduction remains the prominent advantage of Acoustic glass, its merits extend beyond auditory tranquillity. This contemporary glass solution boasts excellent thermal properties, surpassing conventional single glazing. Its thickness acts as a thermal barrier, effectively retaining heat within the property and thereby contributing to reduced energy consumption and lower utility bills.

Where is Acoustic Glass Used?

Acoustic glass finds its primary application in environments characterized by high levels of external noise, including buildings situated adjacent to airports, major roadways, or within bustling city centres. In these locations, the installation of acoustic glass often becomes a vital requirement to meet stringent building regulations aimed at soundproofing structures effectively.

While these aforementioned areas represent the typical settings where acoustic glass is prevalent, it is worth noting that homeowners residing in quieter neighbourhoods also opt for its installation. The allure lies in the ability of acoustic glass to create an atmosphere of absolute serenity and tranquillity, even in such tranquil surroundings.

How is Acoustic Glass Different from Double Glazing?

Acoustic glass sets itself apart from double glazing through its distinct composition and superior sound-absorbing properties. While both options typically feature two panes, acoustic glass boasts thicker laminated glass and an additional bonded internal layer that excels at sound absorption.

The thickness of the glass, or any material for that matter, plays a pivotal role in its noise reduction capabilities. This is evident in the fact that walls and internal partitions on roofs are more effective at noise reduction compared to windows and doors.

Although double glazing falls short of the exceptional sound reduction achieved by acoustic glazing or triple glazed, it still offers a substantial improvement over single glazing.

Acoustic Glass Thickness Reduces Noise Pollution and Improves Security

The thickness of acoustic glass serves a dual purpose, enhancing both noise reduction and security measures. A wide variety of acoustic glass is obtainable in multiple dimensions, typically between 6.5mm and 12.8mm thick. While it is possible to obtain even thicker glass options, it is important to consider that increased thickness corresponds to a heavier weight.

Opting for ultra-thick glass proves highly effective in reducing sound transmission. However, it is worth noting that this comes with additional expenses, as most standard window frames may not be compatible with such thickness, necessitating the investment in a suitable window frame.

Different Noise Reduction Glazing Options

When considering glazing options, noise reduction holds significant importance.

Despite its efficiency in blocking noise by up to 50dB (decibels), the acoustic window may not always be the most suitable option for all scenarios. To provide context, a whisper registers around 20dB, normal conversational levels reach approximately 60dB, heavy traffic measures at 80dB, and a car horn can exceed 110 dB.

To assist in making an informed decision, it is valuable to explore the noise reduction and sound insulation capabilities of alternative glazing options.

Single Glazing Soundproofing Properties

When it comes to soundproofing, single glazing proves to be ineffective. Due to its composition of a single pane of often thin glass, it fails to provide substantial barriers against noise infiltration. As a result, sound easily penetrates through single glazing, diminishing its ability to reduce noise.

Generally, single-glazed windows provide approximately 25 decibels of soundproofing.

Secondary Glazing Soundproofing Properties

Secondary glazing, as the name implies, involves the addition of a supplementary layer of glass installed behind an existing single-glazed window. This cost-effective solution offers numerous advantages akin to double glazing, including enhanced energy efficiency, improved EPC rating, heightened security, and superior acoustic performance.

It particularly appeals to owners of listed properties who are restricted from altering their single-glazed windows, providing them with an alternative means of achieving desired improvements. Secondary glazing presents a practical and efficient option for those seeking the benefits of double glazing in such circumstances.

The combination of single glazing with secondary glazing forms a robust defence against unwelcome noise intrusion.

The collective impact of these layers can significantly reduce environmental noise by an impressive range of 31 to 51 dB, providing occupants with a substantial improvement in acoustic insulation.

Standard Double Glazing

In standard double glazing, two glass panes are ingeniously combined, with the interstitial space filled by an insulating layer of gas. Opting for Krypton gas as the insulating medium proves highly advantageous for individuals seeking optimal noise reduction.

Krypton gas, renowned for its superior density compared to other commonly used gases, presents formidable resistance to sound transmission.

The result is a robust acoustic barrier, significantly impeding the passage of sound. With standard double glazing featuring Krypton gas, noise levels can be reduced by approximately 30dB, providing a substantial improvement in acoustic insulation.

Vacuum Double Glazing Noise Reduction Performance

Vacuum double glazing represents a contemporary alternative to conventional double glazing. Diverging from the practice of filling the inter-pane space with gas, vacuum double glazing takes a unique approach by creating a vacuum, eliminating the air between the glass panes.

This innovative design yields an ultra-thin style of double glazing, known for its exceptional energy efficiency and discreet appearance. As a result, it has gained popularity, particularly among listed properties seeking to preserve their historical charm.

Moreover, vacuum double glazing serves as a preferred choice for retrofitting sash windows due to its slim and lightweight nature, seamlessly fitting into Georgian and Victorian sash frames originally designed for single glazing.

Despite its slim profile, the cutting-edge FINEO glass utilized in vacuum double glazing showcases remarkable noise reduction capabilities, diminishing unwanted noise levels by approximately 35 dB. This ensures a tranquil and serene living environment even in the presence of external disturbances.

Triple Glazing – Soundproof Glazing

Triple glazing, as the name suggests, incorporates three glass panes to form a formidable soundproof barrier. The layered composition of multiple glass panes ensures exceptional insulation against unwanted noise.

Similar to vacuum double glazing, triple glazing offers a remarkable reduction in external noise levels, typically achieving a reduction of approximately 35 dB. This significant noise reduction capability contributes to creating a tranquil and peaceful indoor environment, shielding inhabitants from disturbances originating outside the building.

Installation of Acoustic Glass to Existing Sash Windows

This is indeed feasible, but it is crucial to seek professional assistance due to the unique nature of Georgian and Victorian sash windows, which were originally designed for single glazing. But not all types of glass are compatible with sash windows, as they may either be too thick to fit into the sash or too heavy, potentially affecting the normal functioning of the window mechanisms.

Therefore, engaging the expertise of professionals ensures the proper selection and installation of acoustic glass, guaranteeing a seamless integration that aligns with the specific requirements and mechanisms of sash windows.

Sound Insulation of Windows in Grade 2 Listed Properties

Obtaining permission for the installation of acoustic glass can be challenging due to its thickness. As a result, alternative solutions such as vacuum double glazing have gained popularity among owners of listed buildings. Vacuum double glazing offers a thin and discreet profile, preserving the historic elegance of the property while providing sound insulation benefits.

While permission is still required for installing vacuum double glazing, it is generally more likely to be granted compared to acoustic glazing, as it poses minimal impact on the visual aesthetics of the listed property.

Acoustic Glass Thermal Properties Compared to Vacuum Double Glazing

Both acoustic glass and vacuum double glazing exhibit excellent efficiency. They excel in retaining warm air within the property, making them ideal for maintaining a comfortable indoor environment during the winter season and keeping energy bills at a reasonable level—an aspect of concern for many individuals.

To assess the thermal performance of acoustic glass and vacuum double glazing, comparing their U-values provides valuable insights. The U-value indicates the rate at which heat transfers through a material, with lower values indicating superior insulation.

The U-value of acoustic glass is generally around 1.2 W/m2K, while vacuum double glazing demonstrates remarkable thermal efficiency with a U-value of 0.7 W/m2K - nearly the same as triple glazing.

Is Acoustic Glass Worth It?

The increasing noise levels in our modern world, caused by factors such as vehicle traffic and bustling human activity, have made it challenging to escape from constant background noise.

As previously mentioned, this noise not only proves bothersome but can also have adverse effects on our health and hinder a child’s development. Therefore, it becomes essential to mitigate external noise levels in order to enhance our overall quality of life.

While acoustic glass is designed to address this issue, it may not always be the most optimal choice. Acoustic glass can be expensive, and heavy, and may alter the appearance of a home in a way that some homeowners may find undesirable.

An alternative worth considering is vacuum double glazing, which offers excellent noise reduction capabilities while maintaining a thin and discreet profile. This system can easily be installed into pre-existing windows, providing a cost-effective option for anyone who wishes to enhance their windows.


Can you soundproof windows?

is not possible to achieve complete soundproofing for windows, there are effective measures you can take to significantly reduce external noise intrusion and enhance the acoustic insulation of your windows.

These can be installing Everest noise reduction glass, using window seals and weatherstripping, applying soundproof curtains or blinds, adding window inserts or secondary glazing, and enhancing the overall insulation of windows.

What is the purpose of the PVB layer in reducing noise?

The PVB (polyvinyl butyral) layer plays a crucial role in reducing noise transmission through glass windows. Its purpose extends beyond providing structural integrity and safety. Here’s an expanded explanation of the PVB layer and its impact on noise reduction:

The PVB layer, which is situated between the glass panes in laminated glass, serves as a critical component for enhancing acoustic insulation.

Is it possible to install Acoustic glass windows in our schools?

There are times when noise pollution from external sources, such as traffic or nearby construction, can significantly impact the learning environment in schools. Installing Acoustic glass windows is a viable solution to mitigate these noise-related challenges. Here’s an expanded explanation:

The installation of Acoustic glass windows in schools is indeed possible and can offer significant benefits in terms of creating a more conducive learning environment. Acoustic glass is specifically designed to minimize noise intrusion, allowing students and teachers to focus on their activities without being disrupted by external sounds.

For sound insulation do I need to replace it with the new soundproof window?

You don’t need to install entirely new soundproof windows for effective sound insulation. There are alternative solutions that can significantly improve the acoustic performance of your existing windows.

While new soundproof windows are a viable option for achieving optimal sound insulation, it is not always the most practical or cost-effective solution. Replacing windows can be a substantial investment, especially if your current windows are in good condition and meet other functional requirements.

Luckily, it’s possible to upgrade your existing windows to be more soundproof. One popular solution is the installation of secondary glazing. This involves adding an additional layer of glazing to the interior side of your existing windows, creating an extra barrier against noise intrusion.

Secondary glazing can effectively reduce noise levels, offering improved acoustic insulation without the need for complete window replacement.

Can this glazing be used as fire-rated glass?

The right acoustic glazing, although effective in reducing noise transmission, generally lacks the necessary fire resistance ability to be classified as fire-rated glass.

Fire-rated glass is specifically designed and tested to provide a certain level of fire resistance, acting as a barrier against the spread of flames, smoke, and radiant heat during a fire. While acoustic glazing serves its primary purpose of reducing noise intrusion, it is typically not manufactured or certified to meet the rigorous fire safety standards required for fire-rated applications.

How much difference does the thickness of sound-reducing glass make?

Variations in glass thickness from 6.8mm to 12.8mm can have a noticeable influence on a pane’s soundproofing capacity. Consequently, the depth of the glass can have a notable impact on its power to muffle and stop the noise.

Thicker sound-reducing glass generally offers better noise-reduction capabilities compared to thinner glass. As sound waves traverse the air, they strike the glass, inducing it to oscillate. Thicker glass tends to be more rigid, which helps to absorb and dampen these vibrations, thereby reducing the transmission of sound.

What windows are best for soundproofing?

While planting hedges outside the window, installing noise-reducing glazing, and installing wooden shutters can certainly help in reducing noise, the choice of windows themselves also plays a significant role in soundproofing.

Are triple-glazed better than double-glazed windows for soundproofing?

Yes, triple-glazed windows are generally better than double-glazing for soundproofing purposes. Triple-glazed windows provide an additional layer of glass and extra airspace compared to double-glazing, which enhances their sound insulation properties. The extra layer helps to reduce noise transmission further and improve overall soundproofing performance.

About the author

Glen Ramsey, who presently holds the positions of customer support and content manager, is a cherished member of the Sash Window Refurbish team. He is in a unique position to provide advice on all questions pertaining to the renovation of historic windows because he has a wealth of experience in all elements of window renovation, dealing with clients regularly and assisting them in choosing the best window-related course of action. He oversees the creation of information for all of our platforms in his capacity as content manager, including web content and other materials. Glen has witnessed the whole gamut of Sash Window Refurbish's window restoration activities, from our work on significant listed Georgian homes to a wide variety of smaller-scale private residential projects.


My technician Andrew replaced all my sash windows that had rotten sills. Accessing the rotten sills was not an easy task. He explained to me what needed to be done in order to fix the problem. He is a great person and I’m happy that he was the one who did the job. He is reliable, tidy, friendly and very professional. I highly recommend him.



I hired Andrew and Alex a while back to repair my damaged sash windows. They were was very considerate and very patient as he did his job. A few days ago, I had another problem with one of my sash lock keys and I called him again to come and fix the problem. I’m very impressed that Liam responded quickly and he not only fixed the problem but he also gave me a spare key. What a great after sales service!

Alan W.


I’m very impressed with the new windows that Andrew installed and also the reconditioning job that he did on other sash windows. The quality of his work is by far more superior than what we got when we hired another company a few years back. We will certainly hire him again if any window work arises

Kelly (Sleaford)


Our decorator referred us to Andrew because some of the work needed a window expert. Andrew together with our decorator did a fantastic job. The work was done efficiently and to the highest standards. Andrew is understanding, committed and very professional. I recommend him without any hesitation.

Steaven Reader


Alex did a great job in fixing windows in our terraced house. The windows were broken, frames damaged and the wood was also rotten. Alex's job was high quality and he did it pretty fast. I was also very impressed that he was considerate of my son’s asthma condition and maintained cleanliness. Top work.



Andrew just recently replaced three sash windows in my Edwardian house. He also repaired and replaced some sills and draught proofed three windows. In addition to that, he also did some carpentry work. What I like the most about Liam is that he did a clean job. He is very professional and always updated me about the timescales and costs. He also did his job with minimal disruptions. I highly recommend him.

Cris M.