There are many factors to look at when choosing a sound mat for your home or business. You’ll want to look at the reasons behind getting them, whether it’s for regular foot traffic, soundproofing, or to help with acoustics. Here are some factors you should take into account when making your choice:
Sound Reduction vs. Soundproofing
The first step in determining the right sound mat for your project is assessing whether you need sound reduction or soundproofing mats. Both mat styles are key components in sound reduction systems, but they serve different sound-controlling purposes.
Although both are installed as an underlayment, they are made of different materials. The material differences determine how they interact with sound waves.
Sound Reduction Mats
Sound reduction mats are designed to lower unwanted noise levels but not completely eliminate sound waves. They are made of slightly porous materials that absorb sound waves and reduce their impact on the surrounding environment.
The waves penetrate the porous material, and when there is nowhere else for the wave to go, the energy is converted into heat and released. This reduces echoes and reverberation in the treated space.
Soundproofing Mats
Soundproofing mats are made of heavy and dense materials. These dense materials have more mass than porous materials. Mass plays a significant role in how sound waves are affected. High mass mats prevent vibrational transfer of sound waves through the material.
This means the waves are reflected rather than absorbed. This characteristic works well on exteriors rather than on interior sound reduction.
IIC Rating
Impact Insulation Class is an acoustical rating that measures how well an acoustical material designed for building construction reduces impact noise transmission. The test is regulated by ASTM International and conducted by acoustical labs.
Labs use a tapping machine to measure the level of impact noise transmitted through different floor/ceiling assemblies. An IIC rating of 55 is an acceptable rating or Grade B. A rating of 60 or higher is preferred performance or Grade A.
STC Rating
Sound Transmission Class is an acoustical rating in the United States that determines how well a building material absorbs sound, as measured in decibels. Like the IIC rating, the STC rating tests are also performed in acoustical labs and regulated by ASTM International. Conveniently, the numbers for acceptable and preferred STC ratings are the same as IIC ratings.
Thickness
The thickness of the sound mat also affects its effectiveness. Mat thickness determines what type of frequencies it blocks best. Thinner mats are better at blocking noises in high-frequency ranges, Thicker mats perform better at blocking noises in mid- and low-frequency ranges. Determining the frequency levels you hope to block for your chosen application helps you select the right mat thickness.
Sound Mat Density
Density will also affect how your sound mat performs in your chosen application. Density differs from thickness because density measures the mass per unit of volume or area.
High-density mats tend to reflect more sound than they absorb. That’s why high-density materials are often used in exterior soundproofing applications. Mid- or low-density materials work better for absorbing sound and reducing noises in the interior.
This is why frequency levels are also affected by density. Low-density mats are better at reducing a wider range of noise frequencies than high-density mats. A high-density rubber mat reflects interior frequencies, where a more porous sound mat such as cork or fiber would absorb and diffuse them.
Know Your Application
The best way to choose the right sound mat is to know exactly how you plan to use it. If your chosen application is for sound reduction between floors of a high-occupancy building, you will then know you need a material for sound reduction rather than sound proofing.
Then you can look at the acoustic ratings, thickness, and density to determine how those numbers fit your specific sound reduction goals.