Understanding Acoustic Impact Insulation Class

Ensuring Acoustics comfort within buildings has always been a part of design codes and construction regulations. In addition to thermal comfort, adequate ventilation, lighting & views, acoustics also plays a pivotal role in determining well-being within interiors.

Building Acoustics:

Figure 1: Airborne Sound Transmission

Airborne noise is sound that is transmitted through the air, such as traffic noise or people talking in the room next door.

Figure 2: Structure borne Sound Transmission

Impact noise results e.g., from footsteps on a floor, which can be heard in the room below.

Impact Insulation Class (IIC)

  • Impact Insulation Class (IIC) is an acoustical rating used to quantify impact sound absorption and vibration isolation. This rating system is used for floor and ceiling assemblies.
  • Let imagine, you are living in a condo or an apartment, where you hear a lot of noise from the upstairs mostly the back-and-forth footsteps, furniture legs scratching the overhead floor which is transferred to your living room through your ceiling assembly. This is technically called an Impact noise.
  • Assemblies with these acoustical underlays have a higher IIC rating because they block more impact sound. And the IIC ratings are assigned to floor soundproofing underlays not only based on the product’s material, but the floor assembly on which it is installed due to flanking and other mode of transmission.

Higher the IIC, better the impact sound isolation i,e Better Acoustic Comfort”

How do we test it?

Our acoustic field specialist with help of a tapping machine will carry out the test at your place and validate whether the floor assemblies and associated structures possess impact sound insulation characteristics as designed and will assist you with feasible – cost effective recommendation to enhance the acoustic comfort.

For enquires / information contact us at : [email protected]


Conserve Solutions as a leading consultant for Acoustic Solutions it is our responsibility to educate our clients, customers and young professionals in the market. We intend this series of articles to share our interesting experiences, lessons learned, and case studies.

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Akash Boopathi

A Sustainability Professional with 3+ years of experience in the AEC industry. Industry oriented Skills in Sustainability planning, framework implementation, and Compliance monitoring with Voluntary and regulatory standards. In a mission contributing to a greener and resilient future.