26 Industry Experts Reveal the Best Soundproofing Materials & Techniques

You don’t need to be an architect to or an acoustic consultant to learn how to soundproof a room. You can do it yourself at home. The best part is that it doesn’t have to be expensive. There are plenty of cheap soundproofing materials that you can use with good results.

Whether you want to isolate sounds in a room, prevent noise from entering or to absorb echos and reverberations, in today’s post we will explore ways in which you can achieve these tasks easily and cheaply.

Together with Minuca Elena, we reached out to 25 professionals that faced the same problems as you. They are musicians, acoustic consultants and home improvement experts.

In the first part of this article we asked them:

What’s the best soundproofing material or product to soundproof a room?

In the second part of the article we asked them:

What is your favorite technique for preventing noise from entering or leaving a room?

We received a variety of solutions, some are a bit more technical while others are things you can do yourself easily. We hope you can take from this post whatever fits best to your needs.

Best Soundproofing Materials Mentioned by the Experts:

• Sheetrock
• Mass Loaded Vinyl
• Moving Blankets
• Green Glue
• Roxul Mineral Wool Insulation 
• Foam Mattress Toppers
• Foam Factory Acoustic Foam
• Alphasorb Acoustical Panels
• Sound Panels / Acoustic Wedges
• Isolation Booths
• Stonewool
• Medium-density fibreboard / Gypsum
• Fiberglass Insulation
• Johns Manville Mineral Wool Attenuation Fire Batts
• Bass Traps
• Soundproof Curtains
• Mute-X
• QuietRock
• Metal Resilient Channels
• Carpets
• Noise Reduction Underlayment
• Air

What’s the best soundproofing material or product to soundproof a room?

John Lamb – Backbeat Music Academy

It’s complicated. There is no “best” material. Everything has a trade-off. First, there is a difference between soundproofing, where the sound is prevented from traveling into another area (isolation) vs absorption, which strikes to make a room more pleasant to be in. Each has a different set of tools to deal with.

For soundproofing, the goal is to not allow the sound energy to pass into the next room. This is a pretty abstract concept to grasp, however. It may help to image the sound waves as ocean waves, and the air as water. A very loud sound creates very large, powerful waves, like a tsunami. If there is an open channel for the water (air) to flow through, it will move into the next room at near full strength.

Therefore, creating an airtight barrier is very helpful because it seals the water (air) in the room and prevents it from moving to the next room. However, the power of the wave will push on the walls and create an effect very much like a wave-generator at your local swim park. The wall itself will flex to push the air in the next room, in essence, become a giant speaker.

This is to start answering your question. The materials of the wall make a difference. The only feature that really makes a big difference is mass. The heavier the wall, the harder it is for the sound wave to push, and therefore it moves less. Like trying to push a Volkswagen Beetle vs a Ford Explorer by yourself: the Beetle will get moving much faster for the same amount of force.

With this in mind, you can do things like heavy sheetrock, double layers of sheetrock, Mass Loaded Vinyl, Insulation, Heavy blankets, anything really that adds mass to the wall. However, each material has its own independent properties and will affect different frequencies. Some will be better at deadening high frequencies, but worse at lower ones. Others will be the reverse.

However, the very best material for soundproofing is air. If you can create a layer of completely dead air within the wall, the wave-machine effect will push on that pocket of dead air, dissipating the sound energy before it then pushes on the outside of the wall and that then pushes on the air in the next room. To do this, the traditional method is just to build two walls in a process called double studding. Basically, you build two walls with space – usually about an inch – in between them. This creates a zone of dead air and mechanical separation that is the most effective. It is more effective to do this than to take a single wall and add on mass, or even pour a single concrete wall.

There is another type of product that accomplishes something very similar: acoustic glue (e.g. Greenglue). This is the glue that never solidifies. Instead, it remains liquid. You’d use to glue, say, two layers of sheetrock together, and the layer of glue dissipates the energy the same way the dead air space does. This is the principle behind soundproof glass – two layers of glass with the thin layer between it.

Just exactly how you construct it matters, however. The size of the pocket of air will act like a drum, resonating and amplifying a particular set of frequencies. Generally speaking, the smaller the gap, the higher the affected frequencies are. Bigger spaces amplify lower frequencies. So considering the source of what you want to isolate matters. You might build a vocal booth slightly different than you would for a bass booth, for example.

Price is also a major consideration. MLV costs a couple of bucks per square foot, and adding a second wall obviously comes with framing costs, etc. The first question any studio needs to ask is “What degree of soundproofing do I need?” and “What is my budget?”.

For my music school, I went very simple: Double walls with a single layer of sheetrock, and Greenglue between the sheetrock and the studs caulked and sealed to make the middle airtight. I added Roxul insulation for extra mass inside. My needs are light, though. I have a music school, but I control the sound at the source, using Remo Silentstroke drumheads, etc to control the problem. This is to reduce the need for and therefore cost of soundproofing, but also the prevent hearing damage over time.

Adam Chase – Instrument Find

As a professional musician that is in the process of finishing out my own home recording studio, this is a question I have been exploring in depth myself. Fortunately for me, I studied sound engineering in college and have recorded in several recording studios throughout my career as a professional musician.

In my experience, I have seen a wide variety of soundproofing solutions, ranging from easy and cheap do it yourself techniques to more expensive solutions that require some construction and time.

The cheap soundproofing options tend to be seen in the sweatshop style practice spaces found in big cities around the country. This entails lining the walls and ceiling with sound absorption materials.

The cheapest route would be to take foam mattress toppers, also known as “bed egg crates” and glue or staple them around the room and ceiling. Since the foam material absorbs sound well, this solution is a viable option for keeping sound from escaping your space without spending too much money.

I would recommend going with the thicker mattress toppers for better results. Do know, that this is not going to create a dead room or full isolation, this will simply dampen the sound and help from quiet your space a little as foam absorbs sound. If someone is telling you that bed padding is going to create full isolation and stop all the sound in a room from coming or going, they are full of something and it’s not called truth.

Similar to the foam of bed padding are sound panels that are intentionally made for sound dampening that will work a little better than mattress toppers and there are some options that aren’t too expensive. While it’s not quite as cheap as the bed egg crate option, these are typically designed for having properties that serve the natural acoustics of a room without allow sound to bounce or escape the room.

If your goal is not only keeping the sound from escaping your space but also preventing sound from getting into your space, you have a few options. Ideally, you are working with an unfinished space and are contemplating soundproofing before drywall goes up. If this is the case, you have a couple options.

The best option would be to use soundproof insulation. With the use of soundproof insulation, you can prevent sound from coming in or out of your space without having to cover your walls in mattress toppers. If this is the route you take, I would still consider adding sound panels to specific areas of your room after the drywall goes up.

While sound won’t be coming in from the outside or escaping your room, depending on your floors and drywall, sound can bounce inside of your room. By mounting sound panels behind areas like where drums or amps would be, you can minimize the bouncing of frequencies within your room. With the combination of sound panels and soundproof insulation, you will have a great sounding room.

The most expensive option, which is appropriate in certain situations, would be to build a room within a room. This option is typically for creating isolation booths.

Depending on what kind of recording you are doing, this can be appropriate for drums or vocals. Sometimes it is better to record in a large room to get natural reverb and sometimes it is good to have a completely dry (dead) room so that you can add all of your verb is post-production and have a flat tone as your starting point.

An isolation booth is also good for drummers that want to practice but want to make sure that they won’t disturb neighbors or family members. I have also put guitar amps in isolation booths and mic’d the amp in the isolation booth to prevent the amp from bleeding into live mics, i.e. drum mics or vocal mics, when recording live takes with a full band.

To create an isolation booth, you will want to work with a qualified contractor or construction worker. It is possible to create DIY isolation booths, but with the goal of creating a truly soundproof room, it is better to not mess up or else your work with be in vain.

Creating an isolation booth is essentially building a room within a room. You do this to create space between walls and the ceiling to prevent even subtle vibrations from entering the isolated space, known as airspace.

When creating this space you will use soundproof insolation or stonewool in between the double sides of sheetrock, as well as making sure all sides (ceiling and floor included) are padded. I’ve seen great engineers use moving blankets, but it is not the only way. The doors and any windows should be doubled to prevent the escape of sound and ideally, the walls will not be perfectly parallel to prevent sound waves from bouncing.

The isolation booth is a highly debated topic as far as best practices for building or whether to do it yourself, buy a pre-made booth or to hire professional help. To walk you through the step by step in this article would turn this long article into a small book, so I’ll leave you with the advice I’ve written thus far, but I will say, I would always suggest having someone help that has experience in building and in sound design.

If you are looking to keep sound from leaving or entering a room, there’s nothing better than an isolation booth.

Scott Reyns

True soundproofing takes something like a foot of steel-reinforced concrete on all sides; basically a bunker. When I went to make my booth that wasn’t exactly going to be an option, but I got good results with a double-walled build. Industrial insulation, MDF / gypsum, green glue. In my experience, it’s about the combination of materials rather than any single material.

Creating a solid recording space for things like vocals takes mass all around. The walls, floor, ceiling, and the door should all be thick and heavy construction, and tightly sealed. That gives you isolation.

Additionally, lining them with the right material is needed, such as fabric and acoustic foam. Getting a good sound requires creating a sufficiently “dead” space that doesn’t sound too boxy or reflective, so the interior treatment is what gives you absorption.

Artem Volos – Clutch Prep

In our office, we have four video and audio recording studios. As a video content company, it is very important for us to have the best sound insulation to provide the best sound quality in our videos. We’ve tested many insulation materials such as acoustic foam, blankets, and fiberglass.

The best one that worked out for us was actually mineral wool. Mineral wool works great as sound insulation inside the walls, since its easy to cut, it is lightweight and fire resistant. Installing them inside the walls may sound like a tedious process and it is, but once you do that you’ll definitely notice a huge difference. We used Johns Manville Mineral Wool Attenuation Fire Batts, 4″ for this insulation task.

The same material works well outside the walls for sound absorption, especially for acoustic panels and the so-called “Bass traps,” which helped get rid of low-frequency sounds. Just keep in mind that these have to be built carefully since the mineral wool can irritate skin easily and you also don’t want to breathe it in. So make sure to use proper protection while handling this material at all times.

Mella Barnes – Mella Music

I am a full-time session singer at a company called Tunedly, so soundproofing is very important to me. I live on a busy street and found that things like blankets and foam were not doing the trick.

I ended up building my own booth using heavy plywood and Roxul Rockboard insulation. Roxul Rockboard is typically known as a “bass trap” in many studios, meaning that it is primarily used to dampen low-frequency sound. Although it typically isn’t used by itself in soundproofing,

I found that building a whole booth out of it was a great decision as it cuts nearly all semi truck noise and most motorcycle or loud engine noise. It removes almost all of the street noise entirely and serves as a great vocal booth at a fraction of the cost of professional ones.

I had, of course, explored cheaper options such as foam and egg cartons but found that this was the best option for me.

Peter King – Begin Your Drumming

As a drummer, I’ve tried many ways to soundproof different rooms, as you can imagine it’s very hard to not create a lot of noise when playing the drums especially with your bass drum which is 24” in diameter!

I usually start with the basics so if you have an empty room the first thing I’d do is look to get some thick curtains or soundproof curtains; this will help eliminate some sound. Next, I’d fill the room with some dense furniture around the walls. Bookshelves filled with books are surprisingly good.

Finally, if you want to go the full hog acoustic panels can completely minimize the levels of noise pollution. Acoustic panels are dense rectangles filled with noise canceling materials. I personally prefer the fabrics as these can be hung on the walls and look better than the boards.

If you take all the steps above your room’s noise emission should be way lower!

Angelo Frisina – Groove Drummer

In my opinion, the best way to soundproof a room is to build a room within a room.

There should be a small gap between the interior wall and exterior wall with moisture absorbing crystals at the base of the small gap.

This will help isolate the sound within the interior room and any sounds passing through the room gap will be partially absorbed by the crystals. It’s extremely difficult to get 100% soundproofing, but this technique can have almost perfect results.

It’s also a good idea to make sure the room is not perfectly square. Angular rooms with angled walls and ceilings generally have better acoustic characteristics than square rooms. Not only does this help isolate the sound, but it also produces better quality recorded material. Interior materials such as acoustic wedges and mute-x are also good for interior walls. I have used mute-x on my home studio walls and they help dampen the sound and improve overall sound quality, especially for live drums and loud instruments such as an amplified guitar.

Mick Owar – Stomp Studios