How to Soundproof a Wall; Forget about Noisy Neighbors!

So, you live in one of those modern apartments which look great but lack acoustic insulation, meaning that you can hear and even understand what your neighbors are saying.

The party – or shared- walls in these kinds of apartments tend to be thin and hollow and sound has a very easy time getting through them.

This is something that always bugged me, but luckily there are some ways for you to fix this issue which I’m going to discuss in this article.

Table of Contents

  1. Install Drywall
  2. Install Mass Loaded Vinyl
  3. Install Drywall and Mass Loaded Vinyl
  4. Install Noiseproofing Panels
  5. Treat Flanking Noise
  6. Extra Tips

Install Drywall

Installing an extra thick layer of drywall on top of the already existing wall is a great way to lower the amount of sound that can enter the room.

Simply adding another layer will stop the vibrations and the sound quite a bit.

The great thing about this method is that you can do it yourself and save a lot of the money that you would have otherwise spent on hiring a professional.

It will just take a bit of time, patience and some handiwork.

There are a couple of things to take into consideration;

Apply a Noiseproofing Compound

Applying Green Glue Noiseproofing Compound from a 5-Gallon Pail

Before installing the Drywall make sure to apply a generous amount of this Green Glue Noiseproofing Compound (link to Amazon) behind the drywall sheets.

You don’t need to worry about the pattern or how you apply it, simply make sure that it’s evenly distributed.

This Noiseproofing Compound will further reduce sound transmission by a lot, so don’t skip it!

Apply Acoustic Caulk

Once the drywall sheets are in place, it’s time to seal the gaps left between those sheets with this Acoustic Caulk (link to Amazon).

Green Glue is the by far my top recommendation for the Noiseproofing Compound because of its quality, plus it’s actually quite affordable.

When applying acoustic caulk, it’s very important to seal ALL of the gaps.

If even the tiniest of gaps is left unsealed, sound will be able to get in!

Paint the Drywall with Soundproofing Paint

Although this isn’t nearly as important as properly installing the drywall and applying both the Noiseproofing Compound and the Acoustic Caulk, soundproofing paint can still help quite a bit.

Here’s a link to one on Amazon which should get the job done, otherwise you could go to your local hardware store and simply purchase some.

Install Mass Loaded Vinyl

If you don’t feel like going through all the hassle of installing the drywall, then this step might be the one for you.

Note: Mass Loaded Vinyl only comes in black, which means that you would need to get some fabric to cover it up and make it look nice or find some ways to paint over it.

First you will need to purchase some Mass Loaded Vinyl, this one on Amazon is a great choice and also a very affordable one.

Installing mass loaded vinyl on the walls is no easy task since it’s pretty heavy, you will need the assistance of another person.

Take the edge of the MLV and using screws attach it to the corner of the wall first, right against the ceiling, making sure to not leave any gaps between the ceiling and the MLV.

Then just continue screwing it onto the wall.

You should also be applying the same Green glue Noiseproofing Compound I mentioned earlier on the back of the MLV to further increase sound insulation.

Once the MLV has been installed, you should apply Acoustic caulk between the different Vinyl sheets to seal those gaps.

Install the Drywall with the Mass Loaded Vinyl

If your walls are really THAT thin that you can hear anything and everything your neighbors do, then combining the two methods will ensure that you never hear them again.

First install the MLV and then the drywall on top of it.

The Noiseproofing Compound and the Acoustic Caulk should still be used both on the MLV and the Dywall.

Install Noiseproofing Panels

Similar to installing a drywall, you could go for this option which should work pretty well.

Noisestopsystems sell a Wall System made of a combination of products which give the highest noise reduction possible.

It’s designed to add mass, absorption and separation to your walls, which will ensure that not only airborne noise is reduced, but also the vibrations transmitted.

It is especially good for loud voices and music, which is the typical noise in most apartment situations.

Treat Flanking noises

The methods described above work at reducing the direct sound paths, which basically means lowering the amount of noise allowed through the wall directly.

The issue is that in most cases the walls are just part of the problem.

Flanking noise reduction is a lot harder to treat as flanking noise transmission is basically any other path that sound will take to travel through the structure.

This can be through the ceiling, floor, roof structures, service penetrations, air-vents, you name it!

Treating flanking noise in an already existing building is tough because sound is transferred from one structure to another, especially if they are connected, but there are a couple things you can do.

Which are the major Flanking Paths and how to fix this?

There are some common noise pathways which should be considered in order to know where to soundproof;

Floor Framing System

In some constructions there is a joist system that travels under the wall and these floor systems are connected on both sides of the wall.

This means that even though there is no air path for sound to be transmitted, the vibrations generated on one side can easily reach the other side.

Sadly, there isn’t that much you can do other than installing a floor underlayment and a floating floor on top of it.

You could also try Interlocking floor mats like these ones available on Amazon which are super affordable, just make sure to get enough of them to cover the entirety of the room’s floor.

Ceiling Joist System

A similar thing happens with the ceiling since in some cases an attic may be common to both rooms and the noise and vibrations generated in one can easily be transmitted to the next.

The simplest way is to install drywall on the ceiling which should add a bit of insulation, but the vibrations will still be transmitted.

To do this more effectively I’d recommend purchasing sound insulation clips which will help decouple the drywall from the ceiling.

Decoupling in soundproofing involves separating the framing in the ceiling to break the sound pathway, essentially reducing the noise.

Side Walls

This is by far the most common flanking path since the walls are directly connected to one another, which means that sound and vibrations can easily be transmitted through them.

In order to fix this, you will need to soundproof your existing walls which can be done just like I explained earlier, with Drywall, Mass Loaded Vinyl, etc.

Air Vents

Air Vents are excellent at propagating noise for the simple fact that they are a hollow piece of metal connecting different spaces.

You have two easy ways to reduce this kind of noise;

Hang Sound Dampening Materials in front of the Vent

Using sound absorbing materials like acoustic curtains or blankets and hanging them in front of the air vent will decrease the amount of noise allowed into the room.

This is the simplest solution, even though some sound will still be able to get through.

Make a Sound Maze inside the Vent

This one is a bit trickier to accomplish, but it certainly does work.

Sound likes travelling in a straight line, as soon as you build a maze out of sound absorbing materials, like acoustic foam, for it to navigate before it can reach the room, the level of noise that ends up getting in will be drastically lower.

It should look something like this;

Doors

Most doors, especially the new ones which you can find in most modern apartments, are hollow inside or barely filled with some Styrofoam.

This can help with thermal insulation, but not with blocking sound.

Flanking noise can also enter through the door and much more than you’d think, so make sure to properly soundproof the door in order to reduce this.

I’ve written a complete guide on how to Soundproof a Door which should be of great use.

Extra Tips for soundproofing a Shared Wall

Here are a couple extra steps that you can take which don’t involve spending as much and also don’t take up as much of your time;

Use Furniture to your advantage

If you have a big bookcase which you can put against the offending wall, then you should do so.

Bookcases are great at blocking sound because they are made of solid wood, plus filling it up with books can only help.

Install sound absorbing materials

Sound absorbing/deadening materials don’t block sound as much as something like Mass Loaded Vinyl, but they still help reduce the overall level of noise that is allowed in through the wall.

Investing in these BA Series 9 panels can certainly help reduce the noise transmission through the wall.

They don’t block the sound entirely but they will help reduce it a bit, making them ideal for soundproofing a wall that doesn’t need as much insulation.

Regular acoustic panels work the same way, plus they absorb the soundwaves that bounce off the walls inside your apartment, making it feel more silent in general.

If you find both of these options to be too expensive, then you should consider acoustic blankets.

These are extremely cheap and effective and I’d recommend this pack of 12 blankets from Amazon.

Acoustic blankets are one of my favorite sound deadening items mainly because of how versatile they are, plus they are dead cheap!

Lastly you may want to get a thick carpet and place it right in front of the door. This is a good way to at least absorb some of the flanking noise which might enter through the bottom of the door.

Conclusion

Soundproofing an already existing wall isn’t as easy as soundproofing a door or a window, but it is definitely doable.

Installing an extra layer of drywall may be the best choice considering both the cost and how easy it is to do, since you can do it yourself.

If you have the budget and the skill you might want to install the Mass Loaded Vinyl WITH the drywall for added benefits.

Otherwise you might want to give the noiseproofing panels a try, but those are a bit more expensive.

If the noise your neighbors make isn’t completely unbearable and you simply want it a bit lower, then consider the extra steps I described.

If you have any other tips on how to soundproof a wall that I didn’t mention please leave a comment below!

Have a wonderful day!