STC (Sound Transmission Class)

Sound Transmission Class (STC) is a rating that measures how well a building material or assembly, like a wall or ceiling, blocks sound from passing through. A higher STC score indicates better sound insulation, meaning less noise gets through. It's used to evaluate things like walls between apartments or offices to ensure privacy and reduce noise disturbance. The STC score is determined based on how well the material reduces various frequencies of sound, providing a standardized way to compare soundproofing effectiveness across different constructions.