Build a sound proof wall

Sound proofing guides made simple


A Guide to choosing acoustic materials for your wall
When it comes to sound proofing a wall it is much simpler than many websites would lead you to believe. This page will explore the science and try and explain better why we have targeted the solutions we have. Many of the sound proof products you see on the internet can be created yourself.  Please see our step by step guide to all our solutions.

We will offer a step by step guide and you can jump off at any time and explore the individual sound proof solutions in detail.

Step 1  What kind of wall are you sound insulating
Is it a party wall or is it an internal wall or do you want an overview of all our solutions

Step 2  What is the wall made out of.
If it is the party wall it is helpful to know what it is made out of. This can affect your choi
ce of materials to resolve your noise problem. This isn’t as hard as it sounds. Normally buildings built before the war are made of brick. After 1950 they become a bit harder to assess. The thing you want to be on your guard against is breeze block. Read our article on flanking transmission to find out why. If the wall has plasterboard stuck to it with dot and dab this might need removing. In general plastered brick walls are easiest to soundproof.

Step 3  How much space can you afford to  lose
The other question you will need to ask yourself is how much space you can afford to lose with your sound proofing job. A good rule of thumb is that the more space you can lose the better the acoustic performance especially when it comes to the bass frequencies (like deep men’s voices). But don’t panic you can still get a good result with slim line solutions. Another rule of thumb is that slimmer line solutions tend to use specialist materials which cost a bit more.


Quick Guide
For Solid Party walls  choose A slim line 50 mm solution  or a more heavy duty but thicker solution solution up to 150 mm.
So which should you go for? In brief most people wanting to soundproof are living in an urban environment. Losing lots of space is just not practical . So we find most people opt for a simple slim line solution. The thicker wall will produce a better soundproofing result but it does come with a loss of space.
For Stud Walls . There are two ways to go. Either remove one face of the wall and follow our stud wall sound proofing guide. Or just add acoustic panels to the wall.

Is creating a sound proofed wall a DIY job?
The answer to that is Yes. If you have a reasonable set of DIY skills soundproofing is within most peoples reach. We offer advice on fitter however in reality any competent builder or tradesman can install soundproofing. Each of our solutions has a calculator to work out your materials and set on instructions.
For Internal walls  A stud wall upgrade or a solid wall upgrade


Decibels What does it all mean.
Perhaps the most confusing thing about soundproofing is the scale that is used to measure soundproofing. A quick rule of thumb is that for every 10 decibel (dB) improvement you will hear 50% less sound. So 20 dB will be a 75% improvement. Many companies will boast 50 dB +  numbers for their products. This is physically impossible. They will be talking about the performance of their product plus the wall it is stuck to. SO BEWARE!
So any product that improves your situation by 15dB you will be doing well ! The dB scale is not linear so that a sound which is 10dB louder than another is twice as loud to your ear. A sound that is 20dB louder is four times louder to your ear.

Why is my wall so badly sound proofed.
There are many reasons why some walls are so acoustically poor. The most common reason and thankfully the easiest to resolve is the case of Victorian brick walls. These are often really poorly constructed leaving gaps and cracks between them bricks. built in a day when neighbour noise was much less.  So that you might literally have a little plaster work protecting you from neighbour noise. With more modern constructions particularly the 1960's  the materials used were too light to afford sound proofing. Properties built from the 1970's to the till the turn of the century often used very light weight materials with no acoustic protection in mind. Very modern constructions should conform to regulation E and should have a reasonable level of soundproofing.

The science behind noise and soundproofing

Noise is transferred to us in the form of sound waves. Each frequency we hear comes in the form of waves. Now a typical sound might have lots of frequencies that range from low frequency which might be a deep bass music or a man’s voice all the way up to much higher frequencies such as a crying baby, and all the other frequencies in between. Each of these frequencies is producing it's own set  of sound waves that is passing through your wall (ceiling or floor). Now the existing wall you have is believe it or not is acting as a soundproofing surface. But for various reasons it might not be doing a great job. So, when we try to sound proof we try and add acoustic materials which will combat as best we can the whole range of frequencies  of sound that is coming through the wall.

Why is some sound easier to hear than others?
We need to distinguish between the loudness of the noise and the frequency (pitch) of the noise.In general as sounds of the same volume pass though a wall the low bass frequencies will penetrate the wall easier than the high frequencies. Low frequency sounds lose less energy as they enter a wall. This is for two reason their longer wavelength and the fact that low frequency sounds create resonance in walls and this helps propagate the passage of sound. The problem with a standard brick wall is that it vibrates at a certain frequency allowing much easier penetration of certain frequencies (normally bass or low frequency) Our acoustic wall treatments materials aim to tackle this resonance problem head on.

Frequencies and Wavelengths and why some sound is harder to combat than others.
Each of those frequencies have a different wave length. The deeper the sound you are hearing the longer the wave length.  The noise from neighbours people hear is invariably  lower frequencies. Now in order to disrupt the passage of sound we want to disrupt right across the whole frequency spectrum especially those low frequency sounds. When tackling low frequency sound you can tackle in tow ways. Firstly increase the thickness of the wall. However very low frequency sound can have a wavelength of 5m or more. So while making thicker walls will improve things more from a low frequency perspective it cant be the realistic solution for most people. The Second method that a succeful wall soundproofing solution will focus on is the introduction of many different materials that will act to break up the resonance in walls and effectively absorb the sound as it passes through the wall.

So the two take ways here are yes make your wall thicker but also soundproof smarter.

"Thicker"
So our highest performing solutions will tend to make the wall thicker. Often increasing the soundproofing barrier by 50 to 100%. These independent sound proof stud walls are not always the most practical solution from a space loss perspective especially in smaller urban accommodation where every inch of living space is highly values
"Smarter"
What do we mean by smarter. The materials we want to use have to try and fulfill a few key rolls in a very limited space.
Smarter materials combine; 1) Mass, 2) Resilience  & 3) 
Absorption
Mass
The most well known law of soundproofing is the Mass Law. Which states that by doubling the weight of the acoustic barrier you will gain roughly a 6db improvement in sound reduction. In other words if you doubled the size of your brick wall separation you would get around a 30-40% improvement in soundproofing.  This is why just gluing a couple of layers soundproofing plasterboard direct to a wall will JUST NOT WORK! In addition you will not have in any way addressed the problem of the resonance of a brick wall
Resilience
We have to add the mass of above in a much more smart way. The need to make it springy so that when the sound waves hit it it vibrates and it absorbs passing energy. The old school method of creating resilience was resilient bars. Corrugated steel bars onto which heavy plasterboard is mounted. However it was quite quickly found that rubber mounted bars do a better job as rubber dissipates vibration much better than steel hence GenieClips. Acoustic membranes can act in this way as well
Absorption
But Better still combining resilient layers with materials that have their own internal resilience. So adding products which are intrinsically heavy and resilient makes sense. The SBx board as sand filled board that vibrates easily throughout its structure and rubber layers such as the SM20 mat. These products are non uniform throughout their structure and will absorb this sound energy. 

So back to our sound waves. Before soundproofing all the sound waves hit the wall. The high frequency waves it the wall and are more easily absorbed. The low frequency  sound pass though the wall easily and actually cause the wall to resonate helping ease the passage of sound. 
Now the same  sounds hit  the smart sound proofed wall. The wall is a bit thicker this blocks the waves. The sound wave is encountering multiple different types of mass and potentially air gaps. The sound is absorbed in the wall the wall cannot resonate as one any more as the resonant frequency of the applied materials are very different to the original heavy brick.
This science of soundproofing is now somewhat of an art we bring together multiple products that work differently to maximize the possibility of successfully sound proofing your wall. All we attempt to do at SoundStop is ask you to think how much space you can afford to lose and how much budget that you wish to put to work. we then offer the best solutions for your particular circumstance.

 
HOW TO SOUNDPROOF A WALL STEP BY STEP GUIDE

Should you choose not to go for a stick on solution then here is a quick overview on how to build a sound proofed stud wall.
1)  Create the stud structure. This can be made from metal or from timber . For smaller walls  up to2.4m you can use 50mm stud work. Higher walls generally would use 70-75mm thick studs.  We have a more  guide to creating a stud wall here.
2) Line the stud structure with acoustic mineral wool. This comes in slabs of 0.6m x 1.2m. The recommended density is 60kg/m3 and is easily cut with a hand saw
3) On to the face of the wall you add a resilient layer. This resilient layer will contribute around a third of the overall perfomanace of the wall. A standard wall will use reileint bars a suprerior perfomance wall will use GenieClips.
4) To this resilient layer add a layer of acoustic plasterboard
5) As an optional upgrade an acoustic membrane can now be added.
6) Add a second layer of acoustic plasterboard thus creating a double layer of plasterboard
7) Seal the perimeter with and acoustic sealant.
8) Dry Line or Plaster the wall to finish