for its higher sound transmission class (STC) value. Soundproof drywall in combination with a viscoelastic compound may achieve a noise reduction of STC 60+.

Walls are filled with mineral wool insulation. Depending on the desired level of treatment, two layers of insulation may be required. Outlets, light switches, and electrical boxes are weak points in any given soundproofing treatment. Electrical boxes should be wrapped in clay or putty and backed with MLV. After switch plates, outlet