Soundproofing Your Wall

by: Robert W. Orther

When soundproofing a wall, a lot depends on what sort of noise your were trying to block or absorb. For example, if you were trying to stop a neighbor’s loud television noise from coming through the wall into your unit then you would use a barrier material to block the TV noise. Now if you were concerned about your loud music bothering a next-door neighbor, then both a barrier and a damping material would be in order. There are many different methods for soundproofing a wall from neighbors or just from common out-door sound such as aircraft or traffic noise.

If you are working with newly constructed walls that are only framed out and not yet dry walled, you would want to install a layer of sound batt insulation between the stud cavities. This insulation would be a mineral wool, a rock wool or cotton batt insulation and not common fiberglass batts. Once you have filled the cavities with the sound batt insulation you have a choice of products that will be the soundproofing horsepower, so to speak, for the wall. One of the best barrier materials on the market today is a product called American mass loaded vinylÔ. American mass loaded vinylÔ is a loaded vinyl mat that is impregnated with barium salts and silica to give it mass and allow it to emulate lead sheeting. The Mass loaded vinyl; MLV for short would be stapled or nailed directly to the studs. You’ll caulk all of the seams as well as the entire perimeter with acoustical caulk. Acoustical caulk remains pliant throughout the life of the caulk and it also maintains the STC (sound transmission class) of the MLV at all of the seams as well as around the perimeter of the MLV. Once you have caulked the seams and the perimeter, you will then tape over the caulked seams with a seam sealer tape. This will insure a tight seal of the MLV membrane on the wall. After the MLV is completely sealed, you will then drywall over top of the vinyl membrane with a layer of 5/8” drywall. This system is very effective at soundproofing a common wall between condo or apartment units.

There is another method for soundproofing a common between two units where the drywall is already installed and the owner does not want to remove the existing drywall.

This method would require the use of a damping product called “Green GlueÔ” Green GlueÔ I a visco elastic damping compound that is applied between 2 layers of drywall or gypsum. You would apply the Green GlueÔ using a large quart size caulk gun. The minimum recommended amount is 2 of the 29 oz tubes per 4’ X 8’ sheet of drywall. You would lay out the drywall onto sawhorses and then apply the Green GlueÔ to the back side of the new drywall. Once the glue is applied, you would then screw the new drywall right over top of the existing wallboard whatever it may be. Two tubes per sheet of drywall is the minimum, but 3 tubes per sheet is much better. I suggest using 3 tubes of Green GlueÔ per sheet of drywall for all wall and ceiling applications. These soundproofing techniques will work for home and commercial studios as well as home theaters and music practice areas.

I truly hope this has helped you to understand the science behind soundproofing a wall in a apartment or condo setting.