Acoustic Fiberglass

Acoustic Fiberglass in Soundproofing

Fiberglass has to be one of the best choices for soundproofing. It is helpful to soundproof walls, ceilings, and floors in closed spaces like music production studios. Acoustic fiberglass, as a form of audio insulation, consists of rather small particles of compressed glass or plastic. In order to make this soundproofing material, the sand is heated and then spun at high speeds in order to form glass. It is also common that some manufacturers of acoustic fiberglass use recycled glass to produce the mentioned material. The common forms of fiberglass used for soundproofing come in the form of batts or rolls. Other common areas that usually fill attics and ceilings have a somewhat loose-fill form. Also, it comes in rigid boards and insulation explicitly made for ductwork.  

Thermal Isolation

Fiberglass conducts thermal isolation; therefore, it stops the transfer of heat, cold, and, most importantly, in this case, the sound. The isolation properties of fiberglass further tap down the temperature and soundwaves and prevent them from passing through. Another interesting fact about fiberglass material is that it will absorb the sound and not block or reflect it as some soundproofing materials do.  

NRC Rating

The noise Reduction Coefficient measures the amount of sound a certain material absorbs. The values for rating the materials vary from 0 to 1. Fiberglass is rated from 0.90 to 0.95, so we can say that it works pretty well when rated for sound reduction. Furthermore, STC (Sound Transmission Class) compares how well windows, doors, floors, walls, and ceilings are at reducing sound transmission. It measures the decibel (dB) decrease as sound passes through or is absorbed or blocked by material or wall. For example, a quiet home has an STC 40 rating. The International Building Code (IBC) recommends a rating of STC 50 for walls, ceilings, and floors as a minimum requirement. An increase to STC 55 or STC 60 would be better. Using standard 3-1/2” thick fiberglass batts in wall cavities can improve the STC from a rating of 35 to 39. The sound that travels through drywall is further reduced before it transfers into the next room.  

The Thicker, the Better

As mentioned above, rigid fiberglass insulation helps to reduce noise by absorbing sound. The thicker and denser the batt or roll of rigid fiberglass, the better it will absorb the noise. It is one of the best soundproofing materials, but it will not stop noises 100 %. Bearing this in mind, fiberglass insulation is efficient at absorbing sound and makes a pretty decent sound barrier.  

Source Texts

• Best Soundproofing Insulation for Noise Reduction