Rolls of sound-control membrane in place at a job site in Santa Barbara, CA.


An installer puts his back into smoothing out cementitious concrete placed over the sound membrane.
Since I last wrote about sound abatement, the demand for sound control has increased dramatically. Increasing numbers of municipalities are establishing sound-related regulations and, as end user demand continues to grow, builders and developers are taking the initiative to incorporate sound-abatement systems during the building process to thereby increase the value of their buildings. This is especially true of apartment and condominium construction.

Sound-rating values are the result of a combination of components. A single product or system will not produce the desired results. Rather, the builder must assemble a “package” that works to the desired effect. This package includes the substrate, underlayment, bonding material, flooring, and the ceiling systems below.

Most municipalities request that sound-control tests be conducted by independent laboratories that describe the package used, and certify the results for Impact Insulation Class (IIC) and Sound Transmission Class (STC).

The IIC measures the reduction, from room to room, in noise caused by an object or foot hitting the floor. The STC measures the reduction in airborne noise, such as sounds emanating from a television, conversation or radio.

The Tile Council of America’s 2000 Handbook for Ceramic Tile Installation has accepted into detail RF900-2K a number of ceramic flooring systems for ceramic tile over wood and concrete subfloors. Both thick-bed (mud) and thin-bed (dry-set mortar or latex-Portland cement mortar) systems are included.

Products currently available

A variety of manufacturers produce sound-control products for floor systems. I’ll mention several that may be worthy of your consideration.

Colbond Geosynthetics is a newcomer to the industry, weighing in with Enkatherm, a product that is basically a thinner version of Enkasonic.

The Noble Co., a manufacturer of sheet membrane systems, produces a sound isolation sheet (SIS). SIS is made of chlorinated polyethylene and, at with a thickness of 3/64 inch, is one of the thinnest products available.

The Hacker Sound Mat from Hacker Industries Inc. is designed for use under gypsum poured underlayments, as is Maxxon Corp’s new Acousti-Mat II, a nylon core of fused-entangle filaments. (Note: major gypsum poured underlayment producers estimate that acoustical mats, which currently are used in 10-15% of all poured floors, will be used in more than 20% of all poured floors within five years.)

N.A.C. Products produces a sound control sheet called SAM, or Sound Abatement Mat, which is a bitumen-modified sheet. For use under thin-bed and mortar-bed installations, Kinetics Noise Control has developed a sound barrier called Kinetics SR Floor Board.

Cork Sound Control liners are available from Wicander Corp. and Amorin Industrial Solutions. Homasote, Dodge-Regupol, and General Foam also produce sound-abatement products.

A number of other manufacturers provide sound-deadening materials. I apologize to those firms that I have not named in this article. Certainly, it is not my intent to purposely exclude anyone.

As I mentioned before, you should consult the TCA handbook for references as to the use of cleavage and waterproofing membranes, cementitious backer units, polyethylene foam, and rubber sheets. Remember, it is important not to skip the use of acoustical sealant around the perimeters.

Obviously, a multitude of factors must be considered when selecting a sound-abatement system. For instance, have the product and system been tested independently? What clearance is required? What is the total square-foot cost of each system? How many parts does the system require? How labor intensive and time consuming will the installation be? What are the products’ long-term effects on tile and marble bonds?

I urge you to investigate these questions and research available products to put together a sound-control package that best suits your needs.