In this article, we will discuss about design and decorative acoustic foam for wall and ceiling. Interesting from a financial point of view, however, they have some flaws.

How Acoustic Wall and Ceiling Foams Work ?

Acoustic foam derives its effectiveness from 3 main elements :

1. Its porosity
2. Its density
3. Its thickness

A foam is a basic material. Sold as acoustic because the nature of the material allows the sound to be absorbed.

A foam must have a structure called “open” to work. If there is no hole, there is no absorption.

Some thermal insulation foams therefore have no acoustic performance from a “soundproofing” or “reverberation” point of view.

In an open-cell foam, sound will be trapped in the cells of the foam. Friction will transform the sound energy into heat and the sound will be attenuated.

The denser the foam, the more cells it contains. Thus, the more it will absorb for the same thickness.

The thicker the foam is, the more it will absorb equally. It will then be able to attenuate important wavelengths. There will thus be an absorption of the bass.

To summarize :

1. A 1cm foam will absorb the high frequencies
2. A 3cm foam will absorb the high and medium
3. A 10cm foam will absorb the high, medium and low frequencies

The functioning of acoustical foams alveolated for wall and ceiling

Alveolated acoustic foams

Acoustic foams correspond to all porous foams.

These foams are derived from petrochemicals.

They allow to contain a larger quantity of air than in an empty volume, just like a sponge.

Standard foams

Standard foam is often made of petroleum plastic. In particular, in polyurethane.

These foams can have spikes, various shapes. This allows to increase the contact surface and therefore the absorption of the treble which is easily attenuated. This allows the sound to be quickly “muffled”.

These shapes are also (and above all) present to give the illusion of a technicality, which is actually non-existent. They make it possible to surf on the wave of preconceived ideas which, in the collective imagination, tends to make people believe that egg boxes have an acoustic efficiency… Of course, this is false.

So, in the background, spikes, waves, triangles… none of these shapes add any performance to a flat foam. On the contrary, the total thickness is often lower. And, as specified above, thickness means better absorption of low frequencies.

Melamine foams

Melamine foam is a porous, open-cell foam just like standard foam.

It is a foam that is often sold as Basotect. The latter is a brand of the BASF Group, a giant in the petrochemical and pesticide industry like Monsanto.

This foam is very brittle and does not have good resilience.

The acoustic performance is similar or even better than that of conventional foams.

Its enormous advantage lies in the fact that it has a good reaction to fire. It does not burn or melt.

Whereas a “normal” foam will ignite if it has not received special treatment.

The applications of acoustic foams

Their nature, very basic, destines its foams:

1. Either to be integrated in an acoustic panel
2. Either to be applied directly on the wall for places where the visual impact would not be important.

Their use will therefore mainly be for :

1. Gamers or gaming
2. Home studio
3. Bedroom

Acoustic foams for gamer or gaming

Acoustic foams can be useful for gamer use.

By absorbing resonances, they provide a certain listening comfort and promote immersion in the game.

Acoustic foams for home recording studio

The acoustic treatment of a recording studio is essential for the quality of music reproduction.

Acoustic foams can, therefore, be an inexpensive solution to improve the acoustics of your studio.

Acoustic foams for bedrooms

Living rooms, especially bedrooms, can have significant reverberations. An acoustic treatment of your bedroom may therefore be essential.

If the decorative side is not a priority for you, acoustic foams can be a good solution to remedy these echoes.

Acoustic foams for professionals

Some foams are fire resistant and can therefore be used by professionals.

However, in reality, this is rarely the case.

Because they are less effective, their use is not recommended for businesses receiving the public. Indeed, the number of people being relatively important, the sound volume is too loud to obtain a correct acoustics.

In the same way, foams are very often sold without acoustic advice.

Acoustic foams for walls and ceilings

Acoustic foams can be attached to the wall or ceiling, often with the help of glues. This will create damage to your walls if you wish to remove them.

However, some are self-adhesive and are therefore more respectful of your walls.

Acoustic panels

What is an acoustic panel?

An acoustic panel has the same function as a foam: it tries to absorb. The main difference is that it tries to do so in a more aesthetic and integrable way, hiding the absorption materials.

Engineering also makes it more efficient. Its cost, on the other hand, is higher.

The choice of an acoustic panel is not always easy. We review, below, all types of products on the market.

Types of acoustic panels

Acoustic frame panels

These acoustic panels work with acoustic foams, mineral wools, natural wools, textile fibers or other types of fibers. The function of these materials is to absorb sound.

These absorbers are placed in a wooden or metal frame and covered with a fabric for the most part.

An acoustic panel is relatively technical. The fact of integrating a wooden or metal frame allows it to give the panel solidity and to be installed with or without an air plenum. This frame will modify the absorption capacity because these materials do not absorb sound and are of structural interest.

Then, a finishing fabric will be added to the complex. It will modify the behavior of the product because it can block the absorption of certain frequencies, especially high frequencies. Some fabrics are called “transonorous” because they let the sound pass through. Other tissues are called “resistive” and will block part of the frequencies.

Acoustic panels without framework

Acoustic panels can also operate without a frame.

These panels often work with semi-rigid materials. They can be made of natural materials that have been post-formed under heat, such as wool felts.

They can also be made of compressed cellulose fibers. This is particularly the case of the famous ceiling tile.

Compressed rock wool panels (knauff type) are also very popular due to their relatively low cost.

Acoustic objects

In the acoustic objects, we will find foam cubes with a fabric. These can be hung or used as a totem pole.

Their main advantage lies in their large volume of contact surface with the air. Moreover, all surfaces add up.

A cube of 40cm side has therefore a contact surface of 0.96m². This is almost the equivalent of a 1mx1m acoustic panel.

The disadvantage is, of course, the placement or the very impacting aspect on the visual.

The so-called “invisible” acoustic panels

Invisible acoustic panels are often designed as building elements.

You have probably seen them before because they are “perforated” panels.

They are often made of veneer or wood, with holes of different diameters that are more or less close together.

Their interest lies in their ability to integrate the decor.

These panels require an expertise of implementation.

Their performance is determined by the number and size of the holes. If they are few in number, the absorption surface will be low and the performance will be just as low.

If there are a lot of holes, the performance will be better, especially on the treble.

It should be noted that this structure with holes creates an effect called “resonator”.

This resonator makes it possible to accentuate the performance in certain frequencies. It “targets” rather the frequencies between 250 and 500hz.