---

Sound Transmission Class (STC)
Measure of resistance of a building element such as a floor or wall to the passage of audible sounds.
The higher the STC number the better the sound barrier:

1/2" (12mm) cork underlayment IIC STC statement.

1/4" (6mm) cork underlayment IIC STC statement.

1/8" (3mm) cork underlayment IIC STC statement.

1/2" (12mm) cork floating IIC report.