How many decibels can sound insulation renovation reduce?

Sound insulation renovation typically reduces noise by 10–30 dB—a range that depends on factors like renovation scope, material quality, noise type, and construction precision. "Complete silence" (0 dB, no sound at all) is not achievable in real-world scenarios, but a "comfortably quiet" environment (35–45 dB, similar to a library or quiet bedroom) is fully attainable.