How soundproofing works?

When we construct a soundproof partition wall, building materials are assembled to maximize the wall's sound attenuation. We accomplish soundproofing objectives by taking advantage of the physical properties of materials.

Approaches to soundproofing

Generally, to reduce airborne noise (speech, music) from penetrating partition walls, the designer can take the following measures:

Sound transmission through walls and other building structures is a complicated physical process. Many scholarly books are written on this subject, for example, Sound Insulation by Carl Hopkins.  However, the following demonstration video by Acoustical Surfaces Inc. shows a useful, easy-to-follow, and well-explained analogy of basic material properties utilized in sound attenuation.

Demonstration of material properties useful in soundproofing.

Do not expect watching this video to make you an expert in sound reduction. Many websites sell specialized acoustical materials. These websites usually provide do-it-yourself guidance and suggest that anyone can install soundproofing products. However, this is rarely true, except perhaps in the simplest of situations. 

Successful sound reduction requires a proper assessment of acoustical needs, an understanding of noise attenuation of existing structures, and knowledge of possible flanking noise paths, ventilation issues, and other potential pitfalls. In most typical soundproofing situations, a homeowner or a contractor should seek expert advice to achieve optimal soundproofing results.