Soundproofing Windows: Everything You Need To Know

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SOUNDPROOFING WINDOWS: EVERYTHING YOU NEED TO KNOW

A lot of people don’t realise how doable soundproofing is today.

The latest advancements in the industry mean you can have gorgeous windows and amazing acoustics, no matter how old or complex your existing timber windows may be. You also won’t have to spend as much money as you think.

Whether you live in the city centre or in the countryside, avoiding noise pollution is a challenge no matter where your property is located.

This is because there are so many sounds that have the power to disrupt your sense of peace and quiet.

Unwanted noise has become a part of modern life.

But, it doesn’t have to be.

If you are tired of the noise, your next step is to learn all about soundproofing the windows in your home.

When you learn the essentials of the soundproofing possibilities that are available today, you’ll be empowered to make a better-informed choice as to how to achieve your goal of reducing noise while preserving the integrity and charm of your windows – all for a great value.

There are different ways to soundproof your windows, not all of which are practical, or even cost-effective.

When you understand all the options available to you, you can choose the best way to soundproof your windows to get the peaceful results you are after.

CONTENTS:

Understanding Noise Pollution

Double Glazing and Your Peace of Mind

New or Retrofit Double Glazing – What’s the Difference?

Why You Shouldn’t Use Secondary Glazing to Soundproof

Why DIY Soundproofing Doesn’t Always Work

How Does Retrofit Double Glazing Reduce Noise?

Can You Custom Soundproof Each Window?

Types of Glass for Soundproofing

Is Laminated or Acoustic Glass Better for Noise Reduction?

Soundproofing Sash Windows

Things You Didn’t Know About Reducing Noise in a Home or Building

The Best Way to Soundproof a Window

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UNDERSTANDING NOISE POLLUTION

Love living in the city but not fond of the sounds of the street and traffic that never seems to sleep? Wish you had a quiet home for work or study?

Even in suburbia and rural areas, sources of noise pollution can be a serious issue.

For young families, anyone with an unconventional schedule, as well as those who are sensitive to sound such as the elderly or anyone facing an illness, reducing noise can be even more essential for having a high quality of life.

As a property owner, soundproofing windows can be a great way to make your commercial or residential space more desirable to tenants.

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In today’s hectic, modern atmosphere, anyone would opt for the promise of peace and serenity from converted windows if they had the choice.

Day-to-day exposure to noise pollution increases stress and anxiety and can cause serious health problems over time if sleep is interrupted.

Some sounds are pleasant. Birds chirping as the sun rises, the soft patter of falling rain.

Noise pollution, on the other hand, refers to those sounds that are unpleasant and disturbing. They may be too loud, ongoing or have the ability to disturb sleep, work or studying.

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Different types of noise pollution include:

Trains and aircraft:

Traffic:

Residing near airports or train tracks can come with a dangerous level of noise pollution. Studies have linked living near an airport with an increased risk of hospital visits and deaths related to heart disease.

Trains can have a decibel level as high as 80 dB when 15 metres away, a level that can lead to possible hearing damage.

This is the most common type of noise pollution that people face.

Living in an urban area, the sounds of heavy trucks rumbling down the street and frequent road traffic become a way of life.

Road traffic can range from an annoying 45 dB to a disturbing 75 dB. Motorcycles and heavy trucks can lead to spikes in the sound level.

Social noise:

Noisy neighbours, people talking outside or chatting on their mobile phone, loud music and parties can all create an annoying level of noise.

When you soundproof your home, you can dissipate the sound waves that can travel into your home and enjoy the quiet you deserve.

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By choosing special acoustic grade glass such as SoundStop, you can increase the acoustic benefits even further, although there may not be enough of an audible difference with acoustic glass to make it worth the extra expense.

You can reduce the noise that is able to enter a building by 50% or more when you use laminated glass panes.

DOUBLE GLAZING AND YOUR PEACE OF MIND

Depending on the thickness and the type of glass used, you can enhance the acoustic performance of your windows.

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Double glazing on its own will cut noise pollution by between 20% and 25%, stopping sounds in the mid to high-frequency range from entering the home. This includes traffic, people talking outside, trains, aircraft and heavy machinery, as well as loud music and other sounds you may encounter in living and working spaces positioned near other homes.

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Double glazing is the process of replacing an existing single pane of glass with an insulated glass unit (IGU). An IGU consists of two panes of glass that are separated by a spacer of 6-18mm that can also be filled with an inert gas like Argon Gas.

Both the glass layers as well as the gap all serve to increase the insulating power of the windows, thus reducing noise and making the windows more energy efficient. The 3mm or 4mm of clear glass that most properties rely upon is simply not enough to block out a lot of the noises that we’re subject to on a daily basis.

The result of double glazing is a vastly enhanced interior space. Quiet, comfortable and better indoor air quality if you have retrofit double glazed windows with a built-in drainage design, which is what you’ll get with Thermawood’s patented dry glazed retrofit double glazing system. system.

With double glazed windows, you can soundproof a building, enjoy energy savings along with the acoustic enhancement and increase the value of any home or commercial space.

However, all double glazing systems are not the same. Depending on whether you go with new double glazed windows or retrofit double glazing, the amount you’ll spend to soundproof your windows will vary by thousands of dollars.

Also, you won’t have the same final aesthetic and function as the installation process is distinctly different.

Which is the better choice for soundproofing your windows?

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NEW WINDOWS OR RETROFIT DOUBLE GLAZING OR RETROFIT DOUBLE GLAZING – WHAT’S THE DIFFERENCE?

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Both new windows and retrofit double glazing will reduce noise and are capable of achieving remarkable acoustic performance.

With either option, you will be able to choose different types of glass for noise reduction such as laminated, acoustic grade, as well as varying thicknesses in order to achieve the soundproofing results you want.

There are critical differences, however, that will dictate the overall functionality of your finished windows, as well as how much you will need to spend in order to soundproof your home.

• New double glazed windows cost about three times as much as a retrofit double glazing system. This is because new double glazing is a whole window overhaul. Retrofitting is a modern system that allows you to convert existing wooden windows in a sustainable, affordable way.

• For retrofit double glazed windows, your existing timber windows remain intact. This allows you to maintain the original character of the home or building, creating a more attractive finish.

• With Thermawood’s unique retrofit double glazing system, the acoustic seals are machined into the windows, providing optimal noise reduction without having to worry about seals that may fall off when the windows are opened. This is a common issue with new double glazed windows, where the seals are often added on.

• New Double Glazed windows do not does not allow you to retain the original aesthetic and function of sash or double hung windows. This is one of the reasons why retrofitting is a better option for soundproofing heritage buildings.

• Retrofit double glazing can only be performed on existing timber windows. New double glazing is suitable for other types of window frames, such as vinyl, composite or metal.

When it comes to soundproofing, both double glazing options give property owners the ability to reduce noise as much as possible for each window in a building.

Retrofit double glazing, however, is much less expensive, has the added aesthetic benefits and full drainage system to achieve longevity.

Retrofitted windows are always beautiful, seamlessly fitting within the character of the existing property.

New double glazed windows may clash with the home or building they are installed into.

You may also be forced to lose the functionality and charm of your existing windows when you have to replace the entire window with new double glazed windows, particularly if you have certain types of windows such as sash windows, traditional wooden windows or any heritage design.

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WHY NOT USE SECONDARY GLAZING FOR SOUNDPROOFING?

Secondary glazing involves putting a sheet of acrylic on the inside of the current window, usually with magnets. This effectively creates a thicker barrier for sound to have to travel through.

For example, if your single glazed window was 4mm and you add 3mm or acrylic, now you have a 7mm thick barrier as well as space in between the glazing.

As you can create a larger gap in between your existing glass and the secondary glaze, it’s possible to achieve decent acoustic performance. The problem is, a lot of people don’t like the way secondary glazing looks. Also, you are not able to use different types of high-performance glass such as acoustic Grade Laminated Glass, Low E glass for Better insulation or a Special, Low E or a special safety glass. Nor can you benefit from the added insulating properties of argon gas, which can be inserted in the space between the double glazed panes.

Due to the re-weighting necessary with sash windows, the acrylic becomes a

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problem, making it almost impossible to use secondary glazing on heritage windows successfully.

This, in addition to the way a secondary glazing changes the aesthetic of a window, is why this is a poor option for soundproofing period windows. Thermawood’s retrofit solution, however, allows you to keep all the character of your heritage window, bringing it into the 21st century as a high-performance window.

What many property owners don’t realise when they opt for secondary glazing is that retrofit double glazing costs about the same as secondary glazing. With retrofitting, you’ll save just as you would by using a more affordable alternative to new double glazed windows, yet can still enjoy the lovely acoustics and aesthetics of high performance retrofitted windows.

WHY DIY SOUNDPROOFING DOESN’T ALWAYS WORK

The other problem is the way they look. You could end up with an unsightly window that actually reduces the value of your property.

If you ruin one aspect of your window through doing it yourself, you may end up with somewhat better acoustics – but you’ll also have a new problem such as poor functionality, condensation issues or overall appearance issues.

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Even if you are a self-described do-it-yourselfer, you may want to think again before soundproofing your windows on your own.

Some people apply a piece of acrylic or glass to the inside of their windows themselves.

Aside from the safety risk (glass is heavy and is not something you want to drop on a foot or ankle), DIY jobs can sacrifice the way the window operates.

This means you can keep your existing windows and enjoy fantastic noise reduction.

Then, Thermawood’s patented drainage system adaptor is installed, as well as the draft and acoustic sealing.

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HOW DOES RETROFIT DOUBLE GLAZING REDUCE NOISE?

With a retrofit double glazing window conversion, you’ll get all the insulation benefits of new double glazed windows, as well as the advantages of retrofitting.

With retrofitting, the single glass pane you have now is removed, without tearing out the entire window frame as with new double glazed window installation.

Instead of removing your current window frame, a small part of the existing frame is removed using Thermawood’s unique tooling, which creates a desired 15-degree slope.

By including acoustic seals into the retrofit design, you’ll get a much greater level of noise reduction while still enjoying flawless functionality.

Then the window beading is attached to complete the retrofit double glazing installation.

Next, the double glazing is installed and the front seal attached.

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What you choose will depend on the source of your noise pollution and how much of a difference you’re after.

For example:

You may want to lower outdoor noise by 20 dB with your windows. A Thermawood professional will explain your options, such as the impact of different grades of glass combined with acoustic sealing, in order to reach that goal.

With a combination of the right type of glass, thickness and acoustic seals, retrofit double glazed windows can create a substantial barrier to noise and create the serene interior you want from your windows.

You can choose from different types of glass to achieve the acoustic performance you want.

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CAN YOU CUSTOMISE EACH WINDOW IN A BUILDING?

When you soundproof your home, you don’t have to use the same type of glass for every window.

It’s easy to achieve the ideal decibel level for each area of a home or building by using thicker glass panes where necessary and choosing a specific type of glass used for its acoustic benefits.

For example:

• Windows that face the street may need more soundproofing than those that look out onto a quiet backyard. • You may want to use a thicker glass for your bedroom windows to ensure the areas where people in your household sleep are perfectly quiet.

At Thermawood, we take the time to look at the type and level of the sound coming from outside to create a tailored plan for soundproofing the entire home or building. We can consider the decibel level outside and inside and then determine which glass will work the best.

*TC = Sound Transmission Glass*Rw = Weighted Sound Reduction Index*PSR = Perceived Sound Reduction is a weighted sound reduction comparison that compares the glass performance as a ratio compared to 3mm float glass.*S = SoundStop - Acoustic Laminated Glass

The Good, Better, Best approach is a simplification of the complexity surrounding the selection of the correct glass to provide the best design solution, and therefore other options not listed on this sheet,and are available from The Thermawood Window Installer.

This way, you can customise each room based on the individual room’s needs.

To give you peace of mind that your converted windows will meet your expectations, we can calculate any rating for whichever glass you are interested in to let you know if you’ll be able to achieve your desired interior decibel level.

Performance date - The following tables compare the STC/Rw data and Perceived Sound Reduction (PSR) for a range of IGU’s. The PSR is a weighted sound reduction comparison that compares the glass performance as a ratio compared to 3mm float glass.

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The goal is to optimise the benefits of your retrofit double glazing system. This means reducing noise with the best soundproofing options for each room, and ensuring other goals are met such as:

• Insulation - Heat Loss;• Condensation;• Solar Control - Heat Gain;• Glare - Visible Light;• Fading - UV Elimination;• Safety - Human Impact;• Security; and• Comfort.

All while maintaining the original style and character of your windows.

There’s no reason to pay for thicker glass for an area of your home that isn’t subject to noticeable noise pollution.

On the other hand, some rooms may require a different type of glass such as laminate or acoustic glass to effectively drown out intense sounds like moving trains or a nearby highway.

We’ll also take into consideration other priorities you may have with your windows such as lowering your energy bills with enhanced thermal insulation and reduced glare.

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Acoustic grade glass is another option for soundproofing. To give you an idea of how effective it is, if you simply combine acoustic glass with acoustic seals, you can reduce your noise level in half. Acoustic glass consists of two sheets of glass with a layer of acoustic resin in between.

With retrofit double glazed laminated or acoustic grade windows, you’ll have a dynamic set of features, all working together to block out sound waves:

• Two glass panes;• Acoustic seals;• Interlayer between sheets of gas for each pane – PVB for laminated and acoustic resin for acoustic grade glass.

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TYPES OF GLASS FOR SOUNDPROOFING

While double glazing with standard glass will reduce noise levels on its own, when you want to soundproof a building or home, you’ll achieve dramatic results by integrating a specific type of glass to help block out the sound.

Laminated and special acoustic grade glass, such as SoundStop, are the glass types used for more complete noise reduction.

Laminated glass is stronger than standard glass and is a Grade Safety Glas and can help to make a property more secure. To make it stronger, there is an interlayer between two layers of glass.

The interlayer is often a clear plastic called polyvinyl butyral (PVB). This PVB interlayer prevents the glass from shattering if it is broken. It also makes laminated glass an excellent choice for soundproofing as it has a vibration dampening effect.

Acoustic glass is available in different thicknesses for greater sound reduction.

Keep in mind, sound isn’t just coming in through your windows. It enters through the doors and walls as well. Even with the best acoustic glass in a retrofit double glazed system, it’s still important to consider the building as a whole.

You can have glass doors converted to improve your property’s acoustics. You can also upgrade to a wooden door. Wood has natural soundproofing properties. The cellular structure of wood helps to convert sound energy into heat energy through frictional and viscous resistance. This is why timber windows are also much better at dampening acoustic vibrations than aluminium or synthetic windows.

You’ll also need to ensure that the rest of the building envelope is designed to reduce noise. Factors you may be overlooking, like open vents in the top of a room, may be letting in unwanted sounds from outside.

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IS LAMINATED OR ACOUSTIC GLASS BETTER FOR SOUNDPROOFING?

Acoustic glass is the most effective type of glass for soundproofing.

However, the decibel rating between standard laminated and acoustic glass isn’t much. This means you may not be able to hear the difference between laminated and acoustic grade glazing.

The human ear needs a difference of at least three decibels in order to even notice a difference.

Because there is a price difference between the two – acoustic grade glass being more expensive – standard laminate is often used for soundproofing.

Which is right for you depends on the source of your noise pollution.

With general street noise and traffic, you’ll probably be fine with laminated glass. For more extreme sounds, such as trains or if you live near an airport, you may opt for a thicker acoustic grade glass in order to fully dampen the acoustic vibrations.

This is where secondary glazing and new double glazed windows are not a good option for soundproofing older timber windows or traditional windows. With secondary glazing, it’s difficult to rebalance the sash weight because the acrylic piece destroys the balance. New double glazed windows requires the whole window to be torn out, which destroys the original window.

Thermawood’s retrofit double glazing system is the best solution for soundproofing sash and double hung windows because it is designed to retain the authentic structure and aesthetic. What happens is the windows are reweighted to restore their original functioning. Thermawood also uses a specialised process to do the acoustic sealing.

Having extensive experience with soundproofing heritage windows, we know exactly where most of the noise and draft will come in through a sash window. We target these areas with acoustic and draft seals. Acoustic seals and mohair are used along the side to eliminate any rattles as well as drafts around the sash. For the parting rail in the middle, underneath the sash and around the staff bead on the inside of the frame, we use an acoustic siding seal.

Through this specialised care for heritage windows, as well as the unique retrofit system, we can achieve fully soundproofed windows that are over a century old, while maintaining the charm, beauty and integrity of the existing window.

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SOUNDPROOFING SASH OR DOUBLE HUNG WINDOWS

When it comes to heritage windows, soundproofing takes more care and skill, as well as respect for the original window structure. Most older buildings, as well as newer properties built in traditional styles such as Regency, Victorian and Georgian homes, use sash windows.

These windows have ‘sashes’, which are the glass frames, that slide up or down or can be opened at the top, the bottom or both. They function with the counterbalancing effect of a cast weight, called a sash weight.

This dynamic has to remain intact to preserve the original integrity of the window.

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OTHER THINGS YOU DIDN’T KNOW ABOUT REDUCING NOISE IN A HOME OR BUILDING

What you may not have realised about soundproofing is that you don’t actually have to give up your current windows.

There is no reason to replace the gorgeous timber windows you already have, nor do you have to put on a secondary glaze. Thermawood’s solution enables you to keep your beautiful heritage windows through retrofitting and our specialised acoustic glazing and Acoustic/Draft sealing.

Another false assumption many people have is that you need to use triple glazing in order to get substantial acoustic benefits. This isn’t true either. Triple glazing is designed for the ultimate insulation of heat in extremely cold environments. This means that it not only stops heat loss, but it also prevents heat gain from coming in.

Triple glazing also requires a thicker window frame in order to support the three panes of glass. It is simply too much window for most buildings and forces you to lose your home’s character and charm, without notable acoustic advantages over double glazing.

THE BEST WAY TO SOUNDPROOF A WINDOW AND EXPERIENCE PURE SOUND

Many property owners assume it is impossible to get the benefits of high-performance windows, without sacrificing the authenticity of their period home.

Or, you may think you have to invest thousands of dollars into new double glazing in order to experience a quiet indoor space.

Don’t let these misconceptions stop you from getting the acoustic benefits you have always wanted. Soundproofing with Thermawood’s patented retrofit double glazing system is an affordable yet powerful method for achieving a calm, peaceful environment.

In many ways, modern society has grown accustomed to noise pollution. The truth is you don’t have to suffer from the annoyance, the disturbances, nor the detrimental impact on our well-being of noise. It’s time to become reacquainted with calm.