Contractors or developers that are considering installing soundproofing should be aware of several key elements of this process apart from knowing which materials work best in which scenarios. There is a large variety of materials that are suitable for soundproofing at varying prices but the way they are fitted in relation to the entire building structure is another key element in ensuring outside noise is minimized. There are a few key soundproofing principles and techniques that are effective in accomplishing the task as they are based on the physics of sound transmission.
It is important to understand that sound absorption is not the same as sound blocking. While absorption is one of the elements of soundproofing, it actually only contributes to the whole effect. Most materials with sound-absorbing qualities are only intended to improve the acoustics of a room. They reduce reverberation but do not block sound from entering or leaving. If you’re looking for effective soundproofing, look at products that are not designed for acoustical room treatment.
The four key principles of good soundproofing are:
1. Mass: Drywall and mass-loaded vinyl are examples of good soundproofing materials as they are thick and heavy, which blocks sound. This is most effective against airborne sound, such as voices, but is not suitable for noises transmitted primarily through the building structure.
2. Damping: The special property of the damping compound is its ability to convert sound energy into heat, which makes the sound abruptly stop. It needs to be applied between two stiff panels (drywall, plywood, or subflooring), which are then screwed together to form a Constrained Layer Damping system. Damping is the most effective of the four elements against low-frequency noise.
3. Decouping: When sound is transmitted through the building structure, a different technique can be applied. Gaps are introduced into parts of the structure to prevent the sound vibration from continuing along on its path.
4. Absorption: Absorption plays a key role in soundproofing, although it has the least effect of the four elements. Acoustical ceiling tile and loosely packed fiberglass insulation are examples of sound absorbers as they provide additional soundproofing.
The four elements work independently of each other, which means that they can be combined in different ways to improve the overall soundproofing quality of the structure. There is always room for improvement if the current system in place does not meet the required soundproofing levels.