How to soundproof an existing stud wall? (5 tips)

In this blog post, we will talk about, “How to soundproof an existing stud wall?”, and discuss types of sounds and the need to soundproof. We will also give a step-by-step guide to soundproofing an existing stud wall.

How to Soundproof an Existing Stud Wall?

The best way to soundproof an existing stud wall is to use a combination of two techniques. Insulating the cavity and using soundboards. 

This sounds simple but there is surely science behind it and you need to know the basics of sound and soundproofing to achieve the desired results. Soundproofing is all about making the right choices, using the right materials, and selecting the right techniques.

To soundproof an existing stud wall, you must give a good thought to it and identify the main cause of the noise problem and the solution you need.

There are many promising ways to soundproof an existing stud wall but you need to find and select the one that suits you the best and satisfies your insulation needs.

Using inadequate materials and improperly insulating the walls can come back to haunt you. In the same way, using excess materials and too-good techniques may also be a problem.

Soundproofing is effective but not all measures and techniques are cheap. You need to have a clear-cut idea of your insulation needs to choose the one that you need. 

Types of Sounds and the Need to Soundproof

There are commonly two types of sounds whose existence disrupts the living environment and advocates the need for insulation. These are airborne sounds and resonance. 

Airborne sounds are the normal sounds that travel through the air from one space to another, such as the sound of television, voice, music, etc. Besides this, when the sound waves strike a solid surface, they turn into vibrations and this creates resonance. 

Normally, our home walls only need to be insulated against these two types of sounds. However, stud walls are different from the regular walls as they are hollow. 

Stud walls have sealed cavities and the presence of cavities is what creates the drum effect. Now, what’s the drum effect? Whenever the sound travels into a sealed cavity, it resonates, echoes, and amplifies. This makes the sound appear louder like the sounds coming from a drum. 

In stud walls, we also need to consider this third type of sound and take the measures needed to soundproof our rooms effectively. We cannot let our stud walls create a drum effect as there’s no way to control or insulate it afterward. 

So, what we need to do is take the most essential element needed to create a drum effect away from the stud walls – Cavity. Let’s talk more about this in the next section!!

Soundproofing an Existing Stud Wall

Now we kind of know what we need to do to soundproof our stud walls. We need to cut off the problem from its roots by removing the cavity with a material that could act as the perfect filler. 

However, there is a way to skip this step and insulate the stud walls without filling the cavity. Although, I wouldn’t recommend it if the need to insulate is high. If you only desire to cut down the flow of sound rather than fully eliminating it, then you can perhaps skip the first step and move on to the next. 

Step 1 – Soundproofing the Cavity

So, let’s first talk about the perfect way to soundproof a stud wall and that’s by insulating the cavity. Stud walls are simply a frame of vertical studs and horizontal supports covered by plasterboards. 

There’s nothing in between the boards along with the depth of the studs. This space is a big cavity for the sound waves to create the drum effect and cause a lot of distraction and disturbance. 

So, what we need to do is fill in this cavity with the right material to make it soundproof. Acoustic insulation is what we need to fill in this cavity and it’s the process that does take a little time but produces amazing results. 

To insulate the stud wall with acoustic insulation, we need to follow these simple three steps;

1) Remove the plasterboard covering the studs from one side of the wall. Ideally, the side where the sound is traveling to rather than the side from which the sound is being generated.

2) In the exposed framework, use acoustic insulation to fill the cavity between the studs of the frame. The acoustic insulation normally takes its place in the frame by friction and stays firmly in position. 

3) Reattach the plasterboard to cover up the internal studs and acoustic insulation. Standard plasterboard is good enough to cover the studs. Although for better insulation I always recommend acoustic grade plasterboards.

Selecting the Right Type of Acoustic Insulation

There is no shortage of materials that can be used as acoustic insulators. However, acoustic mineral wool is perhaps the best based on both the performance and cost. 

Different density wool is required to fill cavities of different sizes. In general, the higher the density better the insulation. However, there is certainly a limit to everything and we can’t just fill the cavities with extraordinarily high-density wool. 

What this does is reverberates the sound back into the source room and this just aggravates the problem. So, it is highly important to find the perfect density.

I suggest a density of around 60kg is perfect for acoustic mineral wool used as a cavity-filler. This is dense enough to restrict the ingress of sound in the second room and not too dense that it results in the reverberation of the sound.  

What are Acoustic Grade Plasterboards?

Acoustic grade plasterboard is nothing but the normal plasterboard with extra mass. Sounds not so special…right? Wrong!! These boards are exceptionally good in restricting sound and act as a secondary insulator. Let’s move to the second step to further understand the importance of mass in soundproofing.

Step 2 – Using SoundBoards

We already know that cavities in the stud wall create a drum effect and it is important to fill these cavities to provide sound insulation. So, what’s the science behind adding mass? 

It’s simple, airborne sounds are only blocked by mass and these are the sounds that create the most disturbance. We need mass to restrict the passage of noise from one space to another. 

Wool is a great material to fill the cavity and eliminate the drum effect but it isn’t heavy or massy…right? We need something heavy to achieve the perfect sound insulation. That’s where SoundBoards come into play!!

What are SoundBoards?

SoundBoards are special boards made to replace the regular lightweight plasterboards. These boards contain multiple layers of material to give them the extra weight needed to be an effective insulator. 

Normally, they have a single layer of plasterboard along with a couple of layers of mass-loaded vinyl, and an extra layer of acoustic foam. In tandem, this creates a system of a solid and thick board to cover the stud wall.

The vinyl layers and plasterboards add up a lot of mass to the system and make it an effective insulator against airborne sounds. But aren’t we forgetting something?? 

Yes, we have forgotten about the resonance or vibration in all this chaos. Not to worry, these SoundBoards also contain a layer of acoustic foam and this is the perfect material to dampen the vibration energy.    

There are multiple types of SoundBoards used for this purpose and its selection depends on the noises in play and the need to insulate. 

What Should I Do?

You know the science, you know the system, and you know the need. The choice is yours. Yes, it is possible to soundproof the stud walls by skipping the first step and using high-quality SoundBoards. 

This surely saves up a great deal of time and energy. It does perform amazingly well but the result and performance could get better by not skipping the first step. 

So, if you want good soundproofing, then skip the first step and jump directly to SoundBoards. However, if you need perfect soundproofing, take everything step-by-step!!  


In this blog post, we talked about, “How to soundproof an existing stud wall?”, and discussed types of sounds and the need to soundproof. We also gave a step-by-step guide to soundproofing an existing stud wall.

Frequently Asked Questions (FAQs): How to Soundproof a Stud Wall?

How do you soundproof a wall that’s already built?

Acoustic materials can help you soundproof an existing wall effectively. It is best to use a combination of materials to achieve the best results. Using a combination of multiple soundproofing techniques works the best.

You can use decoupling or sound-blocking techniques to prevent outdoor noise while sound-absorbing materials work the best to minimize echoing and sound reverberation. 

How do you soundproof an interior wall?

To soundproof the interior wall, you have to rip apart the existing drywalls and even ceiling. Afterward, you have to fill the wall with acoustic insulation material or soundproofing material such as fiberglass or mineral wool. 

Furthermore, you need to add metal strips also called resilient channels to the studs and lastly, you have to fasten the new drywall with the channel.

Does soundproofing work for noisy Neighbours?

Yes, soundproofing works for noisy neighbors if you do it correctly. The goal is to increase mass to help them prevent and block sounds from your neighbor’s house. Adding acoustic insulation to the mix helps you achieve a higher level of sound insulation in your house. You can also soundproof the ceiling for even better results.

Can you soundproof existing walls?

Soundproofing existing walls is essential to make the room perfectly soundproof. Yes, you can soundproof them easily by filling insulation in the cavities and using materials such as acoustic foams or panels.

What can I put on walls to absorb sound?

The goal is to make the wall surface soft as sound bounces back off the hard surfaces. Anything from drywall to hardwood floorings can create an echo in your house. To minimize echo and deaden sounds, you need to place sound-absorbing materials on the wall such as cork, acoustic foam, and sound-deadening curtains.

Do soundproof panels keep noise out?

Acoustic panels or soundproof panels aren’t designed to keep the sound out but are mainly built to absorb sounds and reduce echoing. However, they may aid a bit in blocking external sounds but it is better to use sound-mitigation materials for this purpose.


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