Ratings

It is important to know what different acoustic panel rating terms mean. In simple terms we explain the concept below. Note that the 'higher' the rating, the better the result.

Sound Ratings: What Do "IIC" and "STC" Mean?

NOTE: higher figures are better results.

Sound rating methods have been established by the Federal Housing Administration, which is now Housing and Urban Development, and the National Bureau of Standards. Acoustical testing methods and acceptable sound transmission levels have been established by American Society for Testing and Materials (ASTM) and International Organization for Standardization (ISO).

IIC and STC are numerical ratings in decibels of an assembly’s ability to reduce sound transmission over a limited frequency range. Acoustical products are always tested as part of an assembly which is comprised of all of the component parts that make up a wall or a floor/ceiling. This would include a floor covering (wood, vinyl, carpet), padding or underlayment, sub floor (plywood and floor joists, concrete, gypcrete, etc.), suspended or attached ceiling and any ceiling insulation.

IIC, or Impact Insulation Class, is sound that originates by the impact of two bodies striking each other (for example walking) and is carried through the building structure. Acoustic mats, which are softer and more resilient, isolate the wood flooring from the subfloor. This reduces the transmission of the impact noise to the floor below through the floor/ceiling assembly. It also absorbs some of the impact noise that is transmitted back into the room.

Wood floors are one of the least effective types of flooring in controlling impact noise. Wood floors need to be separated or “floated” on a resilient pad to interrupt the transmission of noise to lower floors and reduce noise back into the room.

STC, or Sound Transmission Class, is sound that is airborne, such as voice, music, television or other sound not attributed to impact. This test measures the sound insulation qualities of a wall or floor/ceiling assembly to airborne sound.

Floor/Ceiling Assembly Ratings

The Sika® AcouBond system tested for the following ratings:*

STC- 60
IIC- 59

*Tested at Riverbank Acoustic Laboratory under a 13/16” engineered floor on 6” concrete with a suspended ceiling.

These are exceptional ratings especially on a low profile 5mm system such as the Sika 05 mat and acoustic adhesive. The Sika system offers many benefits over it's rivals.

One of the essential reasons why many installers and architects now recommend SIKA Acoubond is the clean installation method. It is ideal for building sites or right through to established buildings. After priming the concrete with Sika 156 moisture barrier the floor is installed quickly and easily without needing to wait several days [or weeks] for the acoustic membrane to cure. The slotted mat is very easy to use and it requires very little common sense to install the floor correctly. It is one of the easist systems to use on the planet and yet has the highest rating.

As an example one acoustic floor installation required two weeks for the primer to cure, two weeks for the acoustic membrane to cure and then a further week for installation. Aftera further week the floor was sanded and finished. In all 6 weeks. In Contrast the SIKA Acoubond system has a primer that dries in 18 hours and the floor can then be immediatly installed. In all the process may be reduced from 6 weeks to just over two [2] weeks. All builders, architects and specifiers would do well to take note of this industry leading acoustic system. Acoubond is used strictly with 19mm timbers or engineered panels. Check with Sika if unsure of your application.