Door Soundproofing
Doors are often the greatest source of disruptive noise in a room. Doors tend to have gaps around them and be made from particularly resonant materials. Additionally, many doors are hollow, making them extremely resonant-think about it; a hollow door is basically like a drum. Sound proofing your door can be done to whatever degree you believe necessary.
The simplest form of door soundproofing is to insulate gaps around the door. The brush-type seals won’t work so well, as they are composed of individual fibers. These individual fibers are separate and thus allow air to pass between them. They are, therefore, acoustically transparent. Fin type smoke seals make very good acoustic seals for doors. They may, however, be overkill if your door is one of the hollow, drum-like type. Acoustical doors tend to be expensive, and thus tend to be reserved for sound-critical applications like recording studios, government sites, or administrative offices in factories with lots of heavy machinery.
If you your neighbor’s dog keeps you up all night, you might consider one. Also, if you’re a hi-fi or home theater aficionado, you may be want an acoustical door to protect your family-and even your neighbors-from you. For the ultimate in acoustical isolation, consider installing acoustical double-door. The Sound Transmission Class (STC) describes the acoustic properties of an acoustical door, assigning it a single number. This number indicates sound transmission loss from one side of the door to the other.