There are many construction materials that are advertised as having noise reduction characteristics. Some are highly effective as a soundproofing material, while others have only a slight effect or even make misleading claims. Different noise frequencies and different transmission modes call for different materials installed in different locations; this is where your background knowledge can steer you toward the best solutions for your situation, and keep you from wasting your money and effort on ineffective approaches.

Effective Soundproofing Materials

Here are the most commonly used materials that are effective for soundproofing in walls, floors, and ceilings.

Panels (for walls, floors, and ceilings):

#1 Drywall (also called wallboard, plasterboard, or gypsum board), such as Sheetrock. An excellent and inexpensive source of mass, which is a key element in soundproofing. Drywall is a great cheap soundproofing material.

#2 Damped drywall. Drywall which incorporates a sound damping layer. These panels have superb soundproofing properties. (Note that you can also get the same results more cheaply by creating your own damped drywall, by applying damping compound between two sheets of regular drywall.)

#3 Sound-deadening fiberboard (also call soundboard or acoustical board). Because of their low mass, these are not the best choice for soundproofing walls but are sometimes useful in floors as a spacing layer if the additional mass is not needed. They don't provide damping, decoupling, or absorption.

Mass-loaded vinyl (MLV)

A highly dense, flexible membrane sold. A good source of mass, but expensive. MLV is good for filling gaps, and for wrapping ducts, pipes, and metal columns, where a flexible sound barrier is needed. As a layer in soundproofing walls, floors, and ceilings, there are alternatives that are more effective and cheaper than MLV.

#1 Insulation. Loosely packed fiber provides excellent sound absorption, which is a factor in soundproofing, albeit a minor one. Standard fiberglass insulation is as effective as mineral wool, and much less costly. Foams give great thermal insulation but are actually poor for soundproofing.

#2 Soundproof cloth. While ordinary curtains or blankets won't help with soundproofing, there do exist noise control curtains, like curtains made from soundproof cloth, which are industrial products that incorporate a heavy layer of mass-loaded vinyl.

#3 Damping compound (viscoelastic adhesive). Used as the damping layer between layers of drywall, plywood, or subflooring. This substance is a highly effective and economical noise reducer and is one of the few ways to address the low-frequency noise from music, home theaters, construction machinery, etc.

#4 Acoustical sealant (sometimes called acoustical caulk). Important for sealing seams, to prevent sound leakage. Without proper sealing, the effectiveness of all the other soundproofing components will be dramatically reduced, as the noise will simply find its way through the cracks.

#5 Hardware for decoupling. The correct installation of decoupling hardware is very important. Although decoupling is a highly effective element of soundproofing, note that it can actually increase the transmission of low-frequency noise, by creating a new resonance chamber.

#6 Pre-built units. In addition to raw building supplies, there are also pre-built units such as windows and doors engineered to be soundproof, which work very well and can save you time and money. You can even get a complete portable miniature soundproof room.