Unwanted outside noise can disrupt your peace and tranquillity, making it challenging to relax, concentrate or enjoy your time indoors. Whether you live in a bustling urban environment, near a busy street, or in a noisy neighbourhood, soundproofing your room can significantly improve your quality of life. Within this article, I’d like to share some common construction methods for achieving this whilst also looking at some retrospective soundproofing options, for when expensive construction methods aren’t available.

How Does Sound Travel Through Walls?

Sound travels through walls primarily through vibrations. When a sound wave hits a wall, it causes the wall to vibrate. These vibrations then transmit the sound energy to the other side of the wall, where it is heard as noise.

To mitigate these noises from entering our walls, we have two options:

1. Minimize or eliminate the noise source.
2. Construct a barrier to absorb and deflect vibrations.

It might not always be possible to eliminate external sources of noise. For example a noisy neighbour or a busy road outside, but in some cases, manufacturers or building contractors can employ certain techniques to minimise their impact. As an example, elevator manufacturers can design rubber mounts, install silent motors, decouple walls, increase wall mass and add acoustic insulation to assist with lift noise reduction. This is particularly important in buildings with living accommodation. We can use similar techniques in our soundproofing efforts for both internal and external wall construction. Let’s take a look at some of these in a bit more detail below.

Some Key Techniques to Soundproofing

Soundproofing a room involves creating barriers to block or absorb sound waves, preventing them from entering or leaving a space. An effective soundproofing strategy typically combines the use of hard, dense materials and soft, wool-like materials. Here’s a brief overview and some key steps taken to reduce noise penetration.

Seal Gaps and Cracks

Use weatherstripping, caulk, or acoustic sealant to seal any gaps or cracks in walls, windows, doors and other openings. This low-cost application can significantly reduce sound from leaking in or out.

Add Mass

Increase the mass of walls by using thicker drywall or adding mass-loaded vinyl (MLV) layers. Mass helps block sound transmission. The thicker the wall the better the barrier. The same applies to additional layers. Whether you’re building a new wall or soundproofing and existing one this can be a great technique.

Layering drywall and Using damping materials

Apply damping materials like Green Glue between layers of drywall can add significant acoustic relief for the majority of walls. This process is similar to adding mass to your walls with the added benefit of a cushioned layer. Green Glue is a viscoelastic material, which means that it can store energy and then release it slowly. When sound waves hit Green Glue, they cause the material to vibrate. This vibration absorbs the energy from the sound waves, and the energy is then released as heat. This process of dissipation reduces the amount of sound energy that is transmitted through the Green Glue.

Insulate Walls

Fill wall cavities with soundproof insulation, such as fibreglass or mineral wool. This absorbs sound and minimises its transmission. When designing my garden room I employed a brilliant soundproofing technique with the use of two different types of insulation. I used 50mm PIR insulation boards layered with 50mm Rockwool slabs which created a great sound-deadening barrier.

Incorporate Soft Materials

Cover walls with soft, wool-like materials such as acoustic foam panels or curtains. These materials absorb sound and reduce sound reflections within the room. Have you ever stood in an empty room and listened to the reverberation of sound? Like when you’re in a art gallery and all the noises seem amplified. It’s because the sound is able to bounce off all the hard surfaces with ease. Strategically place furniture, rugs and other soft furnishings can help absorb and diffuse sound waves within a room.

Decouple Walls and Floors

This one is a bit more specialised and often used in specific building construction. The idea is to break the direct connection between surfaces to prevent vibrations and sound waves from travelling through a building’s structure. With the use of resilient channels or sound isolation clips to decouple walls from the structure we can preventing vibrations from traveling through.

Floors and Ceilings

Soundproofing isn’t limited to walls. We can also apply similar strategies to ceilings and floors to minimise sound transmission. Increasing the thickness of the flooring can have very beneficial affects on its ability to reduce the transmission of vibrations. Consider installing solid oak flooring for the best results. Oak is a very dense hardwood which makes for a great acoustic insulator.

External Soundproofing Options

Upgrade Doors and Windows

By replacing standard doors and windows with solid-core doors and double-glazed or laminated windows, we can decrease the ability for sound vibrations to travel through. Solid-core doors are a superior choice for soundproofing due to their dense construction, effectively reducing noise infiltration from the outdoors. Double glazing or even triple glazed windows are not only thermal insulators but also greatly increase acoustic properties.

Greenery

Planting trees or shrubs near your external walls can act as a natural sound barrier, reducing noise pollution.

Soundproof Fencing

If your home has an external wall facing a noisy road, consider adding a soundproof fence or barrier to help block the noise.

Exterior Cladding

Consider adding exterior cladding, such as vinyl siding, to your walls.

Soundproofing On a Budget

Soundproofing doesn’t have to break the bank. If you’re working with a tight budget, there are still effective ways to improve your living space’s acoustic comfort. Here are some budget-friendly soundproofing tips:

1. Start by identifying and sealing any gaps or cracks in walls, windows,and doors using affordable materials like weatherstripping, caulk or foam tape. This simple step can significantly reduce noise infiltration.
2. Draft stoppers or door sweeps can help seal gaps beneath doors, preventing both drafts and sound from creeping in.
3. Hang heavy curtains or blankets over windows and doors to absorb and block sound. These are cost-effective alternatives to specialised acoustic curtains.
4. Covering hard flooring with rugs or carpets can help dampen sound within a room, reducing echoes and sound reflections.
5. Rearrange furniture strategically to create sound barriers and break up sound waves. Placing bookshelves or sofas against walls can help absorb and diffuse sound.
6. Consider making your own acoustic panels using affordable materials like mineral wool insulation and fabric. These panels can be effective at reducing sound reflections in a room.
7. Adding potted plants or placing bushes near windows can act as natural sound barriers, reducing outdoor noise penetration.
8. While not as effective as other methods, soundproofing paint can provide a low-cost option for minor sound reduction on walls and ceilings.
9. Create your own window inserts using materials like foam board and sealant. These inserts can help improve window insulation and reduce external noise.

Keeping sound in

Whilst this article is primarily focused on preventing unwanted sounds entering your room the same techniques can be applied to keep sounds in. If you have a recording studio or are in the music industry you may be looking for ways to keep the sound within your walls, to avoid upsetting neighbours or family members.

Building a Soundproof Garden Office

I always like to cover some of my most popular topics on this site, one of which is garden buildings. I’ve recently built my own garden room and have covered insulation installation details for my designs. My designs always include some level of acoustic insulation which I have demonstrated in this diagram.

Whilst this is a great example of a soundproof garden room we can increase efficiency by doubling up on drywall, adding green glue between layers and increasing the thickness of both insulation and sheet materials.

Conclusion

Soundproofing a room is a valuable investment in creating a peaceful living or working environment. Whether you have the means for comprehensive solutions or need to adhere to a budget, there are effective strategies to suit your needs. By implementing the right combination of techniques, you can significantly reduce unwanted noise, enhancing your overall quality of life in your soundproofed space.