TUTORIALS18 min read
Understanding Sound Insulation: STC, Rw, and Why Walls Don't Block All Frequencies Equally
STC (Sound Transmission Class) and Rw (Weighted Sound Reduction Index) both rate how well a wall blocks sound — but they use different standards, different frequency ranges, and can give different results for the same wall. Here is what each rating means, how they are measured, and which one applies to your project.