Does Double Glazing Reduce Noise? – What’s The Truth?

Noise pollution is a major problem in modern society, especially for those who live near busy roads, airports or other noisy areas. One solution to this problem is double glazing. But Does Double Glazing Reduce Noise? 

Of course, double glazing can reduce noise. Though it might not completely reduce the noise, but it will successfully reduce it to a certain extent. 

Basically, it is the two panes of glass used in double glazing that helps to create an air gap between them, which acts as a barrier to sound waves.

In this article, we will explore the science behind double glazing and its effectiveness in reducing noise pollution.

What is double glazing?

Double glazing is a type of window that has two panes of glass separated by a layer of air or gas. This creates an insulating barrier between the inside and outside of a building, which helps to reduce heat loss and increase energy efficiency. 

Double glazing is commonly used in modern buildings and is also popular in retrofitting older buildings to improve energy efficiency. Literally, double glazing is another type of soundproofing- window soundproofing. 

How does double glazing reduce noise?

Double glazing is effective at reducing noise because it creates an additional layer of insulation between the inside and outside of a building. This insulation helps to absorb and block sound waves, preventing them from passing through the window and entering the building. 

The amount of noise reduction provided by double glazing depends on several factors, including the thickness of the glass, the width of the air or gas gap, and the type of glass used.

How sound waves travel through windows

To understand how double glazing reduces noise, it is important to understand how sound waves travel through windows. Sound waves are vibrations that travel through the air, and they can pass through solid objects like windows. 

When a sound wave hits a window, it causes the glass to vibrate. This vibration then creates additional sound waves that travel through the window and into the building.

The extent to which sound waves can pass through a window depends on several factors, including the frequency and intensity of the sound, the type of glass used in the window, and the thickness of the windowpane. 

Generally, higher-frequency sounds, such as those produced by voices or music, are more easily transmitted through windows than lower-frequency sounds, such as traffic noise or construction sounds.

The type of glass used in the window can also affect how sound waves pass through the window. For example, laminated glass is more effective at reducing noise than standard float glass. 

This is because laminated glass consists of two or more layers of glass with a layer of plastic in between. This plastic layer helps to absorb sound waves and reduce noise levels.

The thickness of the windowpane is another important factor. Thicker glass is better at blocking sound waves than thinner glass. However, increasing the thickness of the glass can also increase the weight and cost of the window, so there is a trade-off to consider.

In summary, sound waves can travel through windows as vibrations that cause the windowpane to vibrate and create additional sound waves. 

The extent to which sound waves pass through a window depends on several factors, including the frequency and intensity of the sound, the type of glass used in the window, and the thickness of the windowpane.

The types of glass used in double glazing

There are several types of glass that can be used in double glazing to reduce noise pollution. Below are the three types of glass used in double glazing we’d be discussing.

• Standard float glass.
• Laminated glass.
• Acoustic glass.

Standard float glass

Standard float glass is the most common type of glass used, but it is not very effective at reducing noise. It is also known as Annealed glass. It is made by heating a mixture of sand, soda ash, and limestone to a high temperature until it melts and then pouring it onto a bed of molten tin. 

As it cools and solidifies, the glass becomes smooth and flat. Standard float glass is relatively inexpensive and widely available, but it is not very effective at reducing noise or insulating a building. But regardless of this, it is widely used recently because it is not expensive and it’s still quite effective for noise reduction.

Laminated glass 

Laminated glass is a more effective option, as it consists of two or more layers of glass with a layer of plastic in between. The plastic layer acts as a sound barrier, absorbing sound waves and reducing noise levels. 

Laminated glass is also effective at reducing heat loss and improving energy efficiency, making it a popular choice for double-glazing in modern buildings. In addition, laminated glass is more resistant to impact and shattering than standard float glass, making it a safer option for windows.

Acoustic glass

This glass is a type of laminated glass that is specifically designed to reduce noise pollution. Acoustic glass has a special interlayer that is thicker than the interlayer used in standard laminated glass. 

This thicker interlayer helps to absorb more sound waves and provides even greater noise reduction. Acoustic glass is often used in areas with high levels of noise pollution, such as near busy roads or airports, or in buildings where sound insulation is especially important, such as recording studios or hospitals.

Note: There are other types of glass that can be used in double glazing, and they are: tinted glass, obscured glass, mirrored glass, tempered glass, and many more. 

Related post: Are soundproofing curtains effective?

What are the factors affecting noise reduction in double glazing?

There are several factors that affect the effectiveness of double glazing in reducing noise pollution. Those factors are as follows:

• Seals.
• Glass type.
• Air gap width.
• Glass thickness.

Seals 

One of the factors that can affect noise reduction in double glazing is seals. Seals are an important component in the noise reduction capability of double glazing. If the seals between the glass panes and the frame are not tight and secure, sound waves can pass through the gaps, reducing the effectiveness of the double glazing.

When sound waves pass through a material such as glass, they cause the glass to vibrate. This vibration creates a secondary wave, which is transmitted through the air on the other side of the glass. When sound waves encounter a gap between the glass and the frame, they can pass through the gap and continue to transmit through the air on the other side of the glass.

Glass type 

The type of glass used in double glazing is another important factor that can affect its noise reduction capability. Different types of glass have different acoustic properties, which can impact their ability to absorb or reflect sound waves.

For instance, there are more than three glasses – but the most common are standard float glass, acoustic glass, and laminated glass, which can be used for double glazing and each has a different thickness. 

Standard float glass is not very effective at reducing noise. This is because it is a thin, rigid material that does not have good acoustic insulation properties. As sound waves pass through float glass, they cause the glass to vibrate, which creates secondary sound waves that are transmitted through the air on the other side of the glass.

Laminated glass, on the other hand, is much more effective at reducing noise. Laminated glass is made up of two or more layers of glass that are bonded together with an interlayer of polyvinyl butyral (PVB) or ethylene-vinyl acetate (EVA). The interlayer helps to dampen sound waves and prevent them from passing through the glass. 

And then, Acoustic glass is made up of multiple layers of glass with different thicknesses and densities. It can reduce noise levels by up to 50%, making it a good choice for buildings located in moderately noisy environments.

Glass thickness

As explained in glass type, the thickness of the glass you choose to use could affect noise reduction in double glazing.

Thicker glass is generally more effective at reducing noise than thinner glass, as it can absorb more sound waves.

Air gap width 

Finally, on my list is the air gap width. If there is a little gap width between the two panes of glass used, it could affect the effort of noise reduction in double glazing. 

The goal or the aim while using the two panes of glass used is a wide air gap width. This is because the wide gap will help to provide a better noise reduction, as it will absorb and disperse sound waves better. 

Final Verdict- Does Double Glazing Reduce Noise?

Double glazing can be used for noise reduction with the use of two panes of glasses having an air gap between them which absorbs sound and reduces noise. 

It is a common window technique that can be considered if you have sleepless nights or your house gets too noisy due to the outside noise coming in. If you decide to go for double glazing, laminated glass is the glass that’s best advised to be used.