There are two broad methods to soundproof walls. One is strategies to use over existing walls without getting down to the level of the studs. The other methods are for walls you’re renovating down to the studs.
For existing walls, these methods include filling the gaps in the wall, acoustic absorption, and creating more mass. If you are building a new wall, consider more extensive methods like decoupling and adding acoustic insulation.
The BBC cites scientific research that suggests loud noises are not just annoying – they can lead to depression, anxiety, and a feeling of helplessness. Therefore, it benefits us to pay attention to the noise in our own homes and try to mitigate the noise where we can.
Questions to Ask Before Soundproofing Walls
Wall soundproofing can be more or less invasive, depending on your needs. Walk through these simple questions to help you consider your project before you begin.
- Budget – How much extra money do I have to direct toward soundproofing my walls?
- Time – Do I have the available time that I need if this is a DIY project?
- Noise – Where is the noise coming out of the room? Is the noise high or low frequency? Is the noise temporary? How loud is the noise?
- Tolerance – Does this noise affect my mood?
Noises in the Home
There are two types of noises that echo throughout your house: airborne sound and structure-borne sound. Airborne sounds like hearing your children talking or the TV from the other room. Structure borne, also called impact noise, is caused when an object strikes a surface and causes vibrations. These vibrations are carried through other surfaces in the building until it reaches your ear.
In order to control both of these types of sound, there are two methods of controlling the amount of noise that you hear: absorption and reduction.
- Absorption – Noise control methods in this category seek to absorb the sound so that it is not transferred further. These methods include using acoustic insulation or foam.
- Reduction – These methods reduce the sound that is coming out of the room or into other rooms by the sound waves from exiting one space and entering another. These include strategies like acoustic caulk to block existing holes.
Soundproofing Walls In Place
If you own a home with existing walls that you don’t want to remove, there are certain strategies that you can use to create a more soundproof room.
Look for the Gaps
Noise will come through any open space available, including gaps in the wall around the light fixtures, the electrical outlets, the windows, and gaps around the doors. Use acoustic caulk to seal any gaps that sound could travel through. One popular option is Green Glue acoustic caulk.
Add weather stripping around the windows and the doors in your walls to close gaps. Weather stripping can stop sound from entering the room and increase energy efficiency.
Hang Acoustic Curtains and Panels on the Walls
Acoustic curtains or panels go along the wall to absorb sound. Acoustic curtains, like those from NICETOWN, are soft and heavy. Manufacturers create these panels using mineral wool insulation and then wrap them in fabric to match room decor.
Increase Mass With Built-Ins
If there is a wall in your home that is more sensitive to noise, add mass to it to reduce sound transmission. A large built-in bookcase filled with books is one possible option. Extend the bookcase from the floor to the ceiling to have the greatest impact.
You can also create mass by adding another layer of sheetrock to an existing wall. For the most sound-reducing material, use soundproof drywall for the top layer. Fabricators make this drywall with a viscoelastic polymer to reduce sound transfer. Popular brands of acoustic drywall include CertainTeed and QuietRock.
Increase the sound-damping qualities of additional layers by using acoustic caulk or Mass-loaded vinyl (MLV) between the walls. MLV comes in a roll that you can cut into the right length. You can hang this on the outside of walls, but it is most effective when you use it between the drywall.
Building a Soundproof Wall from Scratch
If you are building a new wall from scratch or are willing to take a wall down to the studs, you have other methods for wall soundproofing. The important principles for building a soundproof wall from scratch are decoupling, sound absorption, increasing mass, preventing sound leakage, and reducing resonance.
Decoupling is separating two walls to limit the sound vibrations that come from one to the other. There are three ways you can decouple two walls.
- Build Double Studs – Studs are the component of the frame that connects the walls together. Building double studs is creating two stud frames with a gap between them and attaching drywall to the outside of each stud frame. This is effective, but you lose extra space.
- Staggered Studs – For staggered studs, use a wide sill plate on the bottom of the wall with more narrow studs. Attach one stud on the right side of the sill plate. Leave a gap and then attach another stud to the left side. In this way, each stud will attach to just one sheet of drywall and not reach the other side.
- Resilient Channels – You can also build a regular wall with standard studs and attach resilient channels to one side of the stud frame. These channels flex and absorb the vibrations that come through the drywall.
Acoustic or sound insulation for walls is an effective way to absorb noise. Use specific insulation formulated to absorb more sound, like Rockwool crafted from molten rock and minerals. Choose between acoustic insulation slabs or rolls, depending on your ability to fit them between your studs. You can also use standard fiberglass insulation, which also works to absorb noise.
By giving your wall as much mass as you can, you decrease the sound transmission through the wall. You can increase the mass of your walls by using more than one sheet of standard or soundproof drywall.
Preventing Sound Leakage
Caulk these with acoustic caulk. If you are serious about creating soundproof walls, minimize the number of windows and doors on your wall.
Most soundproof walls do not contain glass fixtures, as glass conducts sound well. If you do need to include a door, use an option like a solid core flush door for a tight seal.
Increase Sound Damping
Reduce the resonance of sound by using an acoustic membrane between the layers of drywall. You can use the above-mentioned Mass-loaded vinyl (MLV) or another acoustic compound like Green Glue Noise Compound spread between the layers of drywall.
Frequently Asked Questions (FAQ)FAQ
What does a soundproof wall cost?
According to HomeAdvisor, it costs between $10-$30 per square foot to soundproof a room. So, for a standard 10×12 foot wall, it would cost between $1,200-$3,600 to soundproof this one wall.
What is the easiest way to soundproof walls in an apartment?
For walls in an apartment, you cannot do anything permanent. The best way to soundproof walls on an apartment would be to hang Mass-loaded vinyl along the wall and acoustic panels. You can also add furniture to the wall like large bookcases to increase the mass along the wall. Other options beside the walls are to add more soft furnishings to the room to absorb sounds like plush rugs with thick mats or rubber matting on the floor.
What is the best way to soundproof interior walls?
The best way to soundproof an interior wall is to add another layer of acoustic drywall with an acoustic membrane between the layers. Also, close any air gaps around fixtures with acoustic caulk.
What is the least expensive way to soundproof a wall?
The least expensive soundproofing options you can try are caulking and using acoustic curtains. Adding acoustic panels is more expensive, but they are effective.
Use Multiple Strategies for the Most Soundproof Walls
The best way to soundproof your walls is to increase mass and sound absorption. There are some less expensive methods, but the most effective options will require a larger budget. It is a significant investment, but if you own your home, it is an investment that will pay off many years into the future.