Soundproofing has become more common these days to maintain a peaceful life from the busy and noisy roads. When it comes to soundproofing windows, tempered glass is one of the popular materials for soundproofing.
Is Tempered glass more soundproof than other types? Tempered glass is a good noise insulator in some areas but it is not a soundproof glass. Tempered glass is mostly known for its strength and durability, it is not an ideal solution for soundproofing. Laminated glass is highly preferred when we consider glass for soundproofing.
More than the aesthetic look, people need the glass to soundproof their room or vehicles. While choosing the glass in the parameters like price, and durability, you must consider the noise emission factor too. From little or no noise reduction to providing great results in some situations, here are the complete details about tempered glass sound transmission.
Is Tempered Glass More Soundproof Than Other Types?
Tempered glass is consciously made for durability and for that reason, soundproofing is not given much importance obviously. Tempered glass manufacturers create tempered glass by heating it to the temperature as high as 1150 degrees Fahrenheit to create a surface very strong and suitable for application that needs immense resistance over dust and extreme weather conditions.
Let us know different situations where tempered glass is used for sound-emitting. First, if you test the tempered glass openly in any garden to test the sound emission, probably you might experience a loss of 0 dB. When the tempered glass is used with widows at your home, you could hear almost all the medium sound levels.
And the reason is any tempered glass made with the strong material cannot restrict the sound transmission and when the tempered glass is used with windows and doors, little or no sound emission would be notable.
Loudness: The important concept of sound transmissions through the glass. A loud noise would have large pressure and vibrations. The 3dB sound increase can change all the perspectives of glass characteristics. If the glass can withstand up to certain values, the increased level of noise may create a new headache. You must polish the glass considering all the sequences.
Sound Reduction in tempered glass
Although we know why the tempered glass is made, there is some proven application when the tempered glass eliminates the maximum sound. Even though it is not a good sound emitter as you know for homes, car windshield glass could be one of the highlights that we should talk about.
When the research was about to take place, professors tested sound transmission through the car windows, surprisingly, they noticed unexpected results. And the reason why tempered glass in car windows emitted the sound might depend on various elements like car windows materials and the gap between layers.
At the 2002 international congress and Exposition of Noise control conference, the application where tempered glass that emits sound is presented. Windows with the double layers tempered glass are also good sound emitters. The possible reduction of the sound is good compared to other applications.
The double glazed windows consist of two panes of glass separated by a gap. The air gap between the layers principle is based on the cavity wall that separates wind and dust from the outer wall. You can use double glazed windows with one wall of tempered glass and one wall(layer) of laminated glass for durability and sound emission as well.
Tempered glass vs Toughened glass
We cannot compare toughened glass with the tempering glass because toughened glass is also known as tempered glass after some production methods. Like tempered glass, toughened glass is also made for durability.
Both toughened and tempered glass are made to resist break-ins and to resist wind and flying objects. Toughened glass is five times stronger than the laminated glass. It is also stronger than the regular tempered glass.
Toughened glass made under intense heating and it has more breakthrough resistance than the tempered glass. Tempered glass has heat resistance four to five times stronger than standard glass and can resist high-temperature up to 250°C.
Both the tempered glass and toughened glass breaks into pieces when shattered and laminated glass just falls where it shattered. Bus glasses are made for durability and you could have seen the glass pieces when they are broken.
Tempered glass vs Laminated glass
Different glasses have different concerns like durability, sound emission, dustproof, etc. There is no comparison when we compare two different types of glasses when the motive of manufacturing is different.
So, if durability isn’t your priority, some double glazed laminated glass is the perfect fit for sound emission and when you want to give the priority to durability, tempered glass might be a good fit.
The creation of laminated glass is different from the tempered glass. Laminated glass is created by two panes of standard glass leaving the space in between to cover it with a plastic layer. Here comes the real action, the plastic layer acts as a good sound insulator.
Thus, people who compared the laminated glass with the tempered glass noticed the difference in sound emission. Engineers have the point to make an acoustic cancellation glass and hence, Laminated glass takes birth.
It is not a complete solution for soundproofing, it depends on the applications we use. If you use the laminated glass with windows, you must have the two-layer paned windows.
Laminated glass is more expensive than the tempered glass and in some areas, it is mandatory to use laminated glass in windshields. Tempered glass is strong compared to the laminated glass.[Related Article: 6 Home DIY Tips To Soundproof A Window Cheaply]
How Much Sound Reduction Does Tempered Glass Have?
Some common types of glasses available for car and home windows are laminated, annealed, and tempered. Now, according to your type and need, you can choose anyone, or in some cases, you can use two types of glasses for a single window.
Before taking the glass, understanding the concept of insulation and fabrication used in the glass is more important. Some glasses are made for durability and some glasses are for soundproofing.
The standard type of tempered glass offers only little noise reduction but in some cases like windows and car shielded provide some sound insulation.
Unlike laminated glass, this tempered glass is used at extreme rough conditions like on bus and car windows, industrial appliances, high wind areas, and more. Tempered glass is a flexible and easy solution for durability.
So to the conclusion, the noise reduction you can expect with the plain tempered glass is less or minimum. Tempered glass can pass almost all the sound frequencies through them. If choosing the tempered glass is your priority, you must follow some additional sound dampening techniques to avoid sound through the glass.
A 12mm thickness of the tempered glass can reduce the noise levels up to 20 dB. Vacuum sealed glass can reduce the noise of 25 dB. The double-glazed glass has 28mm thickness, (10mm glass, 10mm space, and 8mm of second glass layer) and it can reduce up to 30 dB which is impressive.
Why should you know STC ratings?
Sound transmission class ratings defined how good glass is partitioned that blocks sound and to reduce noise levels. The ratings are determined by measuring the decibel values of the materials. The higher STC ratings, the better sound insulation results.
For home and office purposes, a standard rating of 35 to 40 STC would be great for better sound cancellation. Industries use more than 40 STC to block most of the sound and it depends on the layers too. The problem that comes with the STC ratings is if walls and glasses are placed with gaps, the noise reduction level decreases. Suppose if you insulate a glass that has 50 STC, it would drop to 35 STC.
|25 to 27 STC
|-TEMPERED GLASS (single 10mm)
-DOUBLE 6 (1/4’’) AND (5/16’’
|Fiberglass single layer type
|Up to 40 STC
|Double-Glazed Glass (With air gap)
|45 to 50 CTC
|Lamination and Double-Glaze Combined
|20 to 51 STC
|42 to 56 STC
|Double laminated-Insulated glass
If you already have the glass for soundproofing and checked the STC ratings, you should get the glass with 10 STC improvements for better results. Usually, a 10 STC rating improvement can reduce the sound by up to 50%.
Tempered glass has a decent STC value but not recommended for orifice purposes. It can be used in light noise areas. But when you wish to use the glass, you could use double laminated glass layers for a better STC rating.
How to Improve Soundproofing of Tempered Glass?
Let’s say tempered glass has the ability to emit the little noise levels, a human can identify the change only after 5 dB. That means the human ear cannot recognize the difference of 3 dB to 5dB and thinks both sounds are the same. You need a special device to manually check the difference.
After proper research, the information gathered here might help you to take out the best from tempered glass. Some people took it as a project to show that even tempered glass can reduce the noise levels and the results are astonishing.
The idea behind this project is to create a barrier between the wall and your space. If the installation is done perfectly, tempered glass windows might be a great setup to fight with the noise.
You can not change the acoustic property of the glass but you can add some layers. First, if the windows are two-layered and have good width, arranging the laminated glass with a distance of 8mm between the two glass layers is the best option. The gap can be air vacuumed or gas-filled.
There are acoustic seals, tapes, and foams that can be used to cover the gaps. Along with the windows, doors, and curtains are also needed to be cross-checked. Once you cover all these things, the next step is to get sound deadening curtains. They are made of thick materials that bounce the sound back. Sound dampening curtains are a great add-on for windows.
Glass thickness effect: The sound that travels from the glass depends on its mass, thickness, and characteristics. The single glass pane thickness cannot increase the characteristic levels. When you use the two panels with extra thickness, the air between the layers may have an impact on sound dampening. But in some cases, thicker glass tends to provide a great sound reduction in some cases.
Which Glass is Best For Noise Reduction?
Overall, Acoustic double glazed glass is the perfect choice for soundproofing compared to all other glasses. Keeping in mind the budget and STC Ratings, laminated double glazed layer glass is also a great choice. Many people use 6.4mm glass as the triple layer but double glazed glass is enough.
Laminated Tempered Glass
Tempered glass can be combined to make laminated glass and then the final glass is also tempered. The PVB sheet must be at the right level to maintain the thickness and resistance characteristics. PVB Sheet is used in the middle of the glass that helps in sticking the pieces of glass when broken.
The process seems to be difficult but proven successful. Most of the emergency exit windows and car manufacturers use laminated tempered glass for both durability and sound dampening. It is one of the finest technologies to combine two different characteristics of glasses.[Related Article: How Soundproof Is Concrete As A Material For Blocking Sound]
Glass is one of the best sound dampening materials we have. If you think the same question, why does no one use glass for the entire soundproof solution? Glass is expensive and can be easily broken compared to walls and bricks. Glass should be used when there is space and budget.
The glass must be used for windows and some doors. You cannot use bricks and concerts for windows. To conduct light and to emit UV radiations and noises, glass is one of the finest materials on the planet.
Among all the glasses, tempered glass might stand at the good protector against break-ins but not on the side of sound dampening solutions. There are so many glasses better than tempered glass in sound dampening.
It doesn’t mean that tempered glass cannot be used for soundproof solutions. There are some applications where tempered glass can be used as a great sound reflector. Examples like car windshield and window doors prove that you CAN use tempered glass but with some additional patchwork.
Soundproofing panels and acoustic glues might help in increasing sound dampening levels but it is up to you to choose over the glasses. Modern technologies combine laminated glass and tempered glass with an air vacuum gap in between the shields.