Sound reducing foam: does it work?
No, sound reducing foam is not soundproofing; it has a low mass, an open cell structure and offers no isolation of sound which are all key for soundproofing. In fact, soundproofing foam is a fake term, it is actually acoustic foam and reduces reverberation (echo) in a room. This is different from soundproofing which blocks noise entering or leaving.
Ultimately, covering your walls in ‘soundproofing foam’ will not reduce noise and does not work. It is designed to make sounds inside a space clearer and reduce amplification by sound continually bouncing around a space.
What does foam do to sound?
Foam will absorb sound if it has an open cell structure, which your egg-box type ‘soundproofing’ foam does. This foam is designed to be stuck to walls and ceilings to reduce the reverberation of noises and improve the attenuation of sounds.
Soundproofing foam, (really called acoustic foam), is often foam in music studios or large cavernous spaces where reverberation causes an issue. Many rooms would benefit from acoustic foam panels on walls as conversations are easier to hear and the volume of the room is lowered.
How does sound reducing foam work?
Sound reducing foam works by absorbing sound waves instead of reflecting them from surface to surface. This means fewer sounds are repeated at any one time and the overall volume in a room is controlled. However, do not confuse acoustic foam with soundproofing wall panels, as soundproofing is completely different.
While foam wall panels can absorb noise, soundproofing panels reflect it to prevent noise from entering or leaving a space. This would actually increase the reverberation in a room, and so that space would require soft furnishings to help control the amplification. If you have an external noise issue that you want to block, or, do not want noise from your room polluting other areas, acoustic foam wall panels will not work. You must use soundproofing panels to block noise.
Is sound reducing foam the same as soundproofing foam?
No, sound reducing foam is not the same as soundproofing foam because soundproofing foam does not exist. This often causes confusion, but, sound reducing foam is really acoustic foam. It looks like egg box foam and it is the kind of thing you see in recording studios.
Why sound reducing foam is not soundproofing
While many people call it soundproofing, this is completely inaccurate (but an easy mistake!). To be soundproofing, it would need to block noise from entering or escaping. While sound reducing foam does make a space quieter, it only achieves this by controlling the reverberation of sound inside a space. It has no effect upon blocking noises from out in or vice versa.
However, most spaces that use sound reducing foam have already been soundproofed (this is in the structure of the walls and not visually obvious), hence, people associate that quietness with foam on the walls. All the foam is doing is preventing echo inside the space and giving that deadened quality to noise. The soundproofing is being achieved by high mass wall panels and potentially and isolation clip and channel system.
Can foam soundproof my room?
Foam cannot soundproof your room as it hasn’t got nearly enough mass and the open cell structure offers no decoupling. To soundproof a room, or wall, the mass needs to be increased so sound is reflected away. Second to this, a decoupling device should be used so the wall and soundproofing panels are physically separated. Sometimes a material can be used for decoupling, such as closed-cell foam which does not allow air (and therefore sound) to pass through by dissipating vibrations within itself.
Recipe for soundproofing your room
- Add high-mass wall panels to reflect airborne noise
- Use isolation technology to decouple structures and reduce pathways for vibrations to travel
- Fill cavities with acoustic mineral wool to prevent reverberations and ‘the drum effect’
Using an isolation clip like the MuteClip will dramatically improve your soundproofing. While the high mass materials can reflect noise, not all sound will be stopped, and, when noise hits the panel, your wall will vibrate (ever so slightly!). By decoupling the panels from your supporting wall, the vibrations are stopped in their tracks. It’s an incredibly effective method for soundproofing a wall and provides excellent results.
The MuteClip creates an air gap that is filled with insulation for extra soundproofing defense. You may think foam could insulate this space, but again it cannot soundproof your wall. Instead, we use acoustic mineral wool of 45kg/m3 or higher which has sufficient mass to add further protection from noise. The slim line clip and channel is a mighty piece of technology able to hold a high mass partition away from your wall with ease.
The best way to stop sound through walls – without using foam
The best way to stop sound coming through your walls is without using foam! We have covered mass, decoupling and absorption, so hopefully you feel confident in knowing that acoustic foam is not good for soundproofing a room. However, using other materials, you can soundproof your room to an amazing quality.
To soundproof walls against high-volume noise, like neighbors with parties or wall-mounted TV’s, you need to use the MuteClip system. These come in different levels to suit your space requirements and budgets, but in effect, these create a new soundproofing partition separate to your wall.
What is a wall soundproofing system?
We attached high-mass products to the clip and channel that are designed to resist a wide variety of frequencies. By using a mix of materials, a broader range of sounds can be blocked. Each high mass material has a ‘resonant frequency’ at which is will vibrate and transmit sound. On a graph, you would see a dip in performance at this point, however, by mixing your layers, the dip can be smoothed.
If, after soundproofing your room, you find that you’ve also got a reverberation issue, then you know just the stuff to use by now! Stick a few foam panels to the walls and enjoy your quiet space.
Is spray foam a soundproofing solution?
Spray foam is not a soundproofing solution as it does not have sufficient mass or decoupling properties. If spray foam did not set solid, it would add a decoupling flex to the two materials it touches. However, as it sets solidly, vibrations can travel straight through. Because there is very low mass to the substance, it cannot reflect frequencies, either.
However, spray foam does ass an all important airtight seal, especially around windows, and that will improve the resistance to sound. Ultimately, as space with something in is going to stop more sound than an open hole! Try opening your window a tiny crack to see just how much more noise gets in through a small space and you’ll see what I mean.
