Insulation provides more effective sound control than drywall alone. If you’ve ever been in a building that had little or no insulation, you probably noticed that you heard a lot more noise from outside than in a well-insulated building. This is because the sound transmission coefficient (STC) of an insulated building is lower. The STC is a calculation of the acoustic performance of a wall or ceiling, and a higher number is better than a lower number. It is widely used to rate interior partitions, ceilings/floors, doors, windows and exterior wall configurations.
Sound waves, like heat, always follows the path of least resistance. If there are leaks in the acoustical insulation, then the wall assembly will not provide a good sound barrier. Weathershield TM because of its dense fibers and ability to fill irregular cavities has excellent sound attenuation properties.
The ability of an insulation for sound proofing is measured by the Sound Transmission Coefficient (STC). Weathershield TM can be used to obtain rating in excess of STC 65 depending on assembly and application.
Noise reduction is achieved in three ways with cellulose.
- The first is that cellulose completely fills cavities leaving few air pockets for sound to travel in.
- The second is the cellulose material’s ability to trap air.
- The significant difference between noise reduction with cellulose and fiberglass is its density. Cellulose is approximately three times denser then fiberglass. This helps deaden the sound through walls and between floor levels.
Acoustical Properties: Weathershield TM, compared to other insulation products, has superior properties for improving noise suppression in walls, floors or ceiling construction. There are four performance factors to consider; mass, damping, absorption and sealing.
- Mass (Density): Increased mass per unit thickness of Weathershield TM compared to other fibrous or foam insulation adds to the overall effectiveness of a wall, floor or ceiling assembly in improving STC (Sound Transmission Coefficient) value.
- Damping: Unlike fibrous batts or foam boards, Weathershield TM incorporates itself as an integral part of a wall, roof or ceiling assembly. The natural ability of Weathershield / ProCell TM to fill crevices and gaps produces a significant improvement in the sound damping characteristics of the assembly.
- Absorption: Weathershield TM, because of the unique porosity of its interwoven fibers, will exhibit a NRC (Noise Reduction Coefficient) of 0.75 at 25 mm (1 inch) thickness. Increased attenuation in both low and high frequency ranges is achieved due to absorption within an enclosed wall or ceiling cavity.
- Sealing: Field reliability of Weathershield TM’s noise reduction capabilities is realized through its natural ability to fill crevices and voids normally occurring in wall, floor, ceiling or attic construction. Weathershield TM will completely seal around complex shapes such as pipes, conduit and electrical boxes thereby ensuring its ability to minimize sound transmission through such interruptions.
Cellulose Insulation is an excellent sound proofing insulation product for homes and all types of buildings.
Many different possible wall, floor and ceiling construction assemblies are available with cellulose insulation. Each wall, floor or ceiling assembly has a different performance for Thermal (R value), Sound (STC) and Fire Resistance. We have a few sample construction assemblies available in our builders section of our website, many other options are also possible. Please contact our technical desk for additional information on the thermal, sound or fire performance possibilities that can be designed using our products.