Frequently asked questions
How do I apply the acoustic foam to the mounting surface?
Acoustic foam can be attached to the substrate using a variety of methods, including contact adhesive spray.
How can I mount the foam without using adhesive?
The acoustic foam can be mounted using pins, nails or tacks. Other ways are to apply the acoustic foam to a board or cloth and handing or mounting the cloth on the wall.
What do I need to stop sound from traveling through a wall (or walls)?
Don't use acoustic foam for this purpose, acoustic foam is good for sound absorbtion but not stopping sound transmission.
How much acoustic foam do I need?
Typical applications call for 25% to 75% coverage, with the average being 50%.
Where should I place my Wedge & Pyramid foam or Bass Absorbers?
For Corner Bass absorbers:
Place 2 in each corner, starting from the ceiling going down.
If you decide to go with 4 bass absorbers in each corner, but the ceiling is higher than 8ft, space the bass absorbers out.
Space the bass absorbers evenly, having the top bass absorber touch the ceiling and the bottom bass absorber touching the floor.
When it is not possible to put the bass absorbers in the corner, you can either put them on the ceiling juncture (proffered), or floor juncture.
For corners that are not 90 degrees, you may want to consider our Male / Female broadband absorbers. (Suggested placement of broadband absorbers are the same as placement of corner bass absorbers)
For Wedge and Pyramid Foam:
Start from the ceiling, and working your way down from there. For most applications, the foam panels do not need to be lower than 2ft - 3ft from the floor.
Placement should be concentrated more around where the sound originates. For the wedge foam, they will perform similar if they are horizontal, vertical, or at a 45 degree angle.
If absolute deadness is not required, we suggest placing the foam in a "checkered" board like pattern.
What does NRC mean?
NRC stands for Noise Reduction Coefficient. The NRC of a material can be found by using either the Reverberation Room Method (ASTM C423) or the Impedance Tube Method (ASTM C384). We use the Reverberation Room Method and the general idea of how this method works is:
1) Approximately 72 sq. ft of material is rested on the floor of a Reverberation Chamber. This chamber usually has all hard concrete surfaces.
2) The change in absorption from the empty room to the room with the material is measured.
3) The changes in sound are measured for octave bands ranging from 125 Hz to 4000Hz, recording the differences in Sabine absorption coefficients. The overall NRC rating is the calculated average of frequencies 250Hz, 500Hz, 1000Hz and 2000Hz.
The higher the NRC rating, the more sound the material can absorb.
What does STC mean?
STC stands fro Sound Transmission Class. This rating is used to compare the acoustic isolation of different materials. The Method used to calculate the STC rating is (ASTM E413) A general idea of how this method works is:
1) Their are 2 rooms, a "source" room which contains a loudspeaker and a "receiver" room which contains a microphone. Between the two rooms is an opening usually sized 8ft by 9ft.
2) In decibels (dB), the sound is recorded from in 1/3-octave bands from 125 Hz to 4000Hz
3) The next step is to record the sound again (same process as above) in decibels (dB) with the material (or materials) completely covering and sealing the opening.
4) Then, the difference between the before and after measurements are calculated and recorded. These measurements are the transmission loss or "TL" of the sound.
5) Lastly, (this may be confusing for some) the transmission is drawn on a graph of 1/3-octave and center frequency versus level in decibels. The STC is the measured curve compared to a reference STC curve. (Exact definition can be found by viewing the ASTM E413 method). The requirements used to "match" the curves are (1) The reference curve shall not exceed the measured transmission loss by more than 8 decibels in any 1/3 octave band and (2) The sum of all "negative discrepancies" shall not exceed 32. Once these requirements are met, the value of the reference curve at 500Hz is read as the STC of the material (or materials).
Are your acoustical products fire retardant?
Yes, all of our acoustical products are fire retardant. All acoustic products have fire retardants chemically added to the foam. They are NOT added to just the surface. ALL acoustical products (charcoal & colors) meet ASTM E84 Class A and California 117 flame retardant specifications. Generally, this means if you were to briefly expose our foam to a flame, the foam will self-extinguish.
What would happen if fire where exposed to your acoustic foam?
Our acoustic foam will smolder and smoke, but it will not burst into flames. And after the source of fire is removed, the foam will "self-extinguish". (Note: FoamAcoustics.com does not encourage exposing our products to extreme heat or fire, and will not be held liable for any injury or loss from the misuse of our products.)
What information is needed to pass my building codes?
Our acoustic foams comply to american standards and have been tested in accordance with ASTM E84 for surface burning. (ASTM E84 is the technical equivilant of NFPA 255 and UL 723.) Our acoustic foam meets a "Class A" or "Class 1". This is accepted by most building codes, but this is your responsibility to check for compliance in your specific location before installation.
What does "Class A" mean when talking about Fire retardant Specifications?
In regards to the surface burning standard ASTM E84, this test calculates two numbers. One is "Flame Spread Index", and the other is "Smoke Developed Index". These numbers determine whether the material is "Class A", "Class B", or "Class C" (or Class 1, Class 2 or Class 3, respectively). Class A represents that the material will not burn or smoke much, and Class C represents that the material will burn heavily and produce even more smoke. Class B will burn a little more than Class A, and also produce slightly more smoke than in Class A.