12 Ways to Soundproof Existing Walls

iUnwanted noise can disrupt our peace and comfort in our homes. Whether it’s the sounds of traffic, noisy neighbors, or even the clatter from within our own homes, soundproofing existing walls can be a valuable solution to create a quieter living environment. Fortunately, soundproofing doesn’t have to involve major renovations or breaking the bank. With the right techniques and materials, you can significantly reduce the intrusion of unwanted noise and enjoy the serenity you deserve.

In this guide, I will explore various methods and strategies for soundproofing existing walls. From simple and cost-effective solutions that you can implement yourself to more advanced techniques that may require professional assistance, we will provide you with a comprehensive overview of the options available.

1. Identify the Source of the Noise

Before you start soundproofing, it’s crucial to pinpoint the source of the noise. Understanding where the noise is coming from will help you determine the most effective soundproofing techniques to use. Common sources of noise include:

Neighbors:

Wall Sharing: If you share a wall with a noisy neighbor, the sound can easily transmit through the common wall. Determine which wall is shared and focus your soundproofing efforts on that specific area.

Type of Noise: Try to identify the type of noise your neighbors are producing. Is it music, conversation, footsteps, or other disturbances? This can help you select the most appropriate soundproofing solutions.

Traffic:

Proximity: The distance from your home to the source of traffic noise matters. The closer you are to a busy road, the more soundproofing you may need.

Window and Door Insulation: In addition to wall soundproofing, consider upgrading your windows and doors with double or triple glazing to reduce traffic noise intrusion.

Appliances:

Location: Locate the appliances responsible for the noise. For example, a noisy refrigerator or washing machine in an adjacent room can be a source of annoyance.

Maintenance: Sometimes, loud appliance noises can be mitigated through maintenance or by isolating them from direct contact with the wall or floor.

External Factors:

Outdoor Noise Sources: Consider external sources like nearby construction sites, airports, or industrial facilities. Noise from these sources can be challenging to mitigate and may require a combination of soundproofing techniques, such as soundproofing windows and walls.

Landscaping: Creating a noise barrier with trees, shrubs, or sound-absorbing materials outdoors can also help reduce the impact of external noise.

2. Seal Gaps and Cracks on the Wall

Start by inspecting the walls and identifying any gaps or cracks where sound might be entering or escaping. Common areas include gaps around windows, doors, electrical outlets, and baseboards, as well as any visible cracks or holes in the wall itself.

Clean the areas around the gaps and cracks to ensure proper adhesion. Use sandpaper to smooth any rough surfaces if necessary.

• For smaller gaps and cracks, apply acoustic sealant directly into the openings. Make sure to fill the gap.
• For larger gaps, use a backer rod first to fill the space partially, and then apply acoustic sealant on top of it. The backer rod provides support and helps the sealant adhere better.

Use a putty knife to smooth the sealant and create a clean, even surface. Make sure it’s flush with the wall or surrounding surfaces. Remove any excess sealant. Apply painter’s tape around the areas where you’ve applied the sealant. This will help protect the surrounding surfaces and create a clean line for finishing.

After the sealant has dried, remove the painter’s tape and inspect the sealed areas. If you missed any gaps or cracks or if there are areas that need additional attention, repeat the sealing process.

If you want the sealed areas to match the existing wall’s appearance, you can paint over the sealed areas once the sealant has fully cured. Be sure to use a paint that matches the color and finish of your existing wall.

3. Add Mass to Existing Walls

Adding mass to existing internal walls is a key strategy for improving soundproofing because it enhances the density and thickness of the wall, making it more effective at blocking and absorbing sound waves.

Sound waves are vibrations that travel through the air and solid materials, and they can easily pass through lightweight or thin walls. When you add mass to a wall, you increase its ability to resist the transmission of these sound waves.

By attaching additional layers of denser materials like thicker drywall or mass-loaded vinyl to the existing wall, you create a barrier that impedes the passage of sound. The added mass helps to absorb and dissipate sound energy, reducing the intensity of noise traveling from one side of the wall to the other. Moreover, applying soundproofing compounds like Green Glue between layers further enhances the soundproofing by damping vibrations and preventing them from passing through.

4. Decoupling Existing Internal Walls

Decoupling involves the separation of two sections within a wall to effectively minimize the transmission of vibrations and prevent the propagation of loud noises through the wall.

This s a highly effective method for improving soundproofing because it disrupts the direct transmission of sound vibrations through the structure of the building. In many cases, sound waves can travel through the building’s framing, which creates a path for noise to pass from one side of the wall to the other. Decoupling involves separating the two sides of the wall, breaking this direct pathway and thereby significantly reducing sound transmission.

To decouple existing walls, you can use techniques like resilient channel installation or sound isolation clips.

Resilient channels are metal strips that are attached horizontally to the wall studs, and then the drywall is attached to these channels instead of directly to the studs. Sound isolation clips work similarly, but they are typically used for ceilings. These methods create a small gap or airspace between the existing wall and the new drywall layer, which isolates the two surfaces and prevents sound vibrations from traveling through the framing.

Decoupling is particularly effective at reducing low-frequency sounds and vibrations, which are often the most challenging to block. It also minimizes the risk of structural flanking paths, where sound can travel through adjacent building elements like floors or ceilings. However, it’s essential to ensure that the decoupled wall is properly sealed and finished to maintain its soundproofing effectiveness.

5. Construct a stud or metal frame over the existing wall

It’s important to understand the significance of decoupling soundproofing from the existing wall to tackle both impact noises and reduce airborne noise effectively. So, how do you go about achieving this, and what represents the most efficient approach?

There is a range of clip and bar soundproofing solutions available on the market, and my recommendation leans towards utilizing the market-leading ReductoClip System.

With the ReductoClip System, you have the flexibility to apply it directly to an existing brick wall. For even better performance, you can attach it to an independent stud frame, positioning it at least 10mm in front of the existing wall. This stud frame connects to the ceiling, floor, and side walls without making contact with the problematic wall that needs soundproofing.

This strategic placement heightens the soundproofing’s effectiveness by introducing an air gap between the problematic wall and the soundproofing material, making it considerably more challenging for sound to pass through.

Following this, you can proceed to attach ReductoClips and furring bars onto the stud frame, further isolating the soundproofing from the existing wall. This configuration represents the pinnacle of soundproofing and finds applications in diverse settings, including music studios and homes, aiming to mitigate excessive noise levels.

The ReductoClip System operates by isolating existing walls, efficiently reducing the transfer of sound vibration energy through the following steps:

• Begin by constructing a timber stud frame at least 10mm ahead of the existing wall.
• Secure ReductoClips and furring bars to the stud frame, effectively decoupling the soundproofing layers.
• Incorporate acoustic mineral wool between the battens of the stud frame, efficiently absorbing airborne sound within the cavity situated between the soundproofing and the existing wall.
• Attach acoustic plasterboard to the furring bars, which boasts 50% greater density than standard plasterboard, thus contributing substantial mass to the existing wall.
• Enhance the soundproofing further by introducing a layer of Tecsound onto the acoustic plasterboard, adding a significant amount of mass.
• Finally, complete the system by adding a second layer of acoustic plasterboard, effectively sandwiching the Tecsound material in between.

6. Add More Mass to Existing Walls Using Furniture

The layout and arrangement of items within your room can significantly impact the level of noise within the space. You have the opportunity to effectively minimize unwanted noise by strategically manipulating the positioning of your furniture and wall fixtures.

One effective strategy is to position large, heavy furniture pieces in close proximity to the walls that require soundproofing. The furniture serves as a sound absorbers, intercepting and dampening sound waves. By placing such furniture pieces near the walls, you can capitalize on their ability to absorb airborne noise that might otherwise penetrate through the walls. However, it’s important to note that when furniture is in direct contact with the walls, it can sometimes transfer vibrations into the room.

To further enhance sound absorption, consider incorporating softer furnishings alongside the heavier pieces. Softer items, such as upholstered chairs or plush cushions, are effective at capturing and diffusing sound waves that manage to pass through the denser furniture.

This combined approach, with both heavy and soft furnishings strategically positioned, can lead to a significant reduction in noise levels within your room. Ultimately, the careful arrangement of your furniture can serve as an efficient and practical method for soundproofing your living space.

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7. Plaster the Existing Main Walls

When dealing with brick walls, conventional soundproofing methods may not be as effective. Nonetheless, there’s a viable solution: plastering the walls. Plastering serves to augment the thickness of your walls, thereby introducing soundproofing attributes.

A single layer of plaster can impart sound-dampening qualities to your wall, mitigating the transmission of noise. To further optimize soundproofing, some individuals choose to apply plaster to both sides of the wall, encompassing both the interior and exterior surfaces. This dual-plastering approach offers enhanced soundproofing capabilities, effectively reducing noise infiltration from both directions.

Incorporating plaster into your soundproofing strategy is a practical and viable option, particularly when confronted with brick walls that may not respond as well to other soundproofing techniques. It’s worth noting that while plastering can help, complete soundproofing may require a combination of methods, depending on the specific sound issues you aim to address.

8. Hang Soundproofing Blankets over your existing internal walls

The noise outside your house may be temporary. Thus, you don’t need a permanent soundproofing solution. In such a case, you can have some acoustic blankets until the noise source is withdrawn.

Referred to as sound barrier curtains, these blankets are designed to block sound and can be hung from movable frames.

Sound blankets and sound barrier curtains function much like sandbags that prevent flooding water. These blankets have weight and density, effectively countering the passage of sound waves through their material. Beyond their density, the fiberglass core padding also serves to absorb the energy that the density inhibits. Consequently, sound blankets represent a hybrid product that not only has the capacity to “block” specific noise sources but also to “absorb” sound waves that are reflected within the environment.

It’s important to note that acoustic blankets are not the same thing as soundproofing blankets. The former is designed to absorb noise (echoes and reverberations), while the latter blocks sound transmission.

9. Hang Soundproof Wallpaper over the walls

Soundproof wallpaper, also known as acoustic wallpaper or sound-absorbing wallpaper, is a type of wall covering designed to reduce noise transmission and improve acoustic comfort within a room. It is a popular choice for homeowners, businesses, and commercial spaces seeking a practical and aesthetically pleasing solution to control noise.

Acoustic wallpapers can help reduce the noise that gets into your house. However, this method will not deaden all the noise from outside. The wallpapers are cheap and easy to install. Thus, you can use it when you are on a tight budget.

You can buy Yataihui Foam wallpapers in large rolls. It helps save on the final cost rather than buying a few pieces at a time. Since the seams where the wallpapers meet are visible, you can apply some sparkle. It adds some glamor and gives the wallpapers a seamless finish.

10. Apply a Coat Of Soundproofing Paint Over Existing Walls

Unlike regular paint, soundproofing paint is specially designed for sound absorption. Like acoustic wallpapers, acoustic paint won’t block noise but absorb sound, especially reverberations and echoes.

Soundproofing paint is one of the easiest methods for soundproofing existing walls. First, applying the paint is similar to using regular paint. You start by applying a primer. It helps in holding the base coat and the paint in place.

Apply a base coat after the primer dries out and let it dry. If you want better results, apply another layer of base coat. Take your soundproofing paint and apply it to the dry base coat. Ensure you stir the paint well before application.

The paint is thicker than normal paint and has a texture. You can achieve better results if you apply two layers of paint. Separate the layers for 40-60 minutes to ensure the first layer has dried off. Finish your work by applying a layer of finishing coat.

11. Hang Soundproofing Foam Panels

If you’ve been to a recording studio, you’d have noticed that the walls are covered with acoustic foam panels. The foam layer helps to reduce echo and keep the recorded voice smooth and clear.

Additionally, soundproofing foam panels prevent the noise from leaving the recording studio into other rooms. One of the most popular foam panels is the self-adhesive acoustic foam panels by Dmsky since they are cheap and easy to install.

They are available in different sizes and colors. Thus, you can get panels that can suit your interior decor. The panels are sold alongside a special adhesive spray to fix them on the wall, making them easier to attach.

12. Add Blown-In Insulation

Blow-in insulation, also known as loose-fill insulation, fills joist cavities or studs with loose material that has insulating and sound absorption properties.

The most common type of blow-in insulation is cellulose material. However, using Styrofoam or fiberglass fibers is highly recommended, especially if you want to achieve both sound and heat insulation.

You can do blow-in insulation yourself; however, you need a professional hand to make perfect blown-in insulation in most cases. The expert uses the right tools to access the spaces between the drywall. They blow in low-density cellulose foam in the loose spaces in the wall.

The foam then traps air pockets within air pockets that block the vibrations of sound waves. These air pockets in the walls are responsible for sound transmission, and filling the pockets or gaps with cellulose or fiberglass will help block airborne noise transfer.

On how to soundproof existing walls

In conclusion, soundproofing an existing wall is a valuable home improvement project that can greatly enhance your quality of life by reducing unwanted noise and increasing privacy. Whether you’re dealing with noisy neighbors, street traffic, or the hustle and bustle of a busy household, there are effective solutions available to help you achieve a quieter and more peaceful living environment.

Remember that the key to successful soundproofing lies in understanding the principles of sound transmission and taking a holistic approach. Start by identifying the weak points in your wall, such as gaps, cracks, or thin materials, and address them first. Then, layer your soundproofing materials strategically to create a barrier that effectively blocks and absorbs sound waves.