Sound Dampening
Importance of Quiet Walls - We've all heard the scornful reference to "paper thin" walls - those walls that allow you to listen in on nearly every sound coming from an adjoining room. And, the obvious negative connotation is that paper thin walls are cheap walls. Aside from code-required sound performance, what should not be lost on anyone is the fact that people inherently recognize and appreciate quiet walls and attach a significant value premium to them. In the construction industry, the effectiveness of sound dampened walls is measured by what is called Sound Transmission Coefficient or "STC" ratings. In fact, the industry, by code, specifies minimum acceptable levels of STC ratings for particular uses. For example (and this is a simplification), party walls between multi-family dwellings require an STC of at least 50; walls separating hotel rooms an STC of 60; and walls for theater applications as high as 70 STC. Even though it may not be code-required, the walls separating luxury condominium units had better reach a 60 STC plus or else the developer/builder will experience never-ending complaints from the residents who expected more given their considerable investment - not to mention damage to the builder's reputation. Noise ranks as the Number One complaint from condo buyers - no big surprise - so good business sense practically demands a strong focus on sound transmission of walls.
Sound Dampening 101 - There are multiple methods for improving the sound performance of walls, the most common being resilient channel (which has been around now for over 50 years); isolation clips (an improvement to the connections made for resilient channel); mass loaded vinyl (MLV) and common fiberglass or mineral wool batt insulation. Since our focus is the quality of the wall construction itself, we won't address here various "sound absorbing" materials which can be added to the surfaces of any wall. Achieving effective sound performance for walls is a matter of finding ways to defeat the vibration that can be transmitted through them. Vibration is what transmits sound. MLV addresses sound transmission by adding mass to the wall. It acts as a "sound blocker." Batt insulation, referred to in the industry as Sound Attenuating Blanket or "SAB" acts as a "sound absorber". And, resilient channel ("RC")and isolation clips take the approach of being "vibration disruptors" that attempt to break the sound wave connection so that the vibration can't fully transmit to the other side of the wall. Today's standard wall construction which connects the drywall panels to the stud framing with mechanical fasteners, typically screws, creates a clear path for vibration through the wall, practically inviting vibration to do its thing. The more screws in the installation, the more rigid the wall, the better the sound transmission through it. RC installations were designed to create a disrupting disconnect between the drywall panel and studs, what is referred to as "decoupling" the drywall panel from the stud framing. SureWalls system was designed to work by this same means (decoupling), but we took aim at two particular drawbacks of RC installation, the first of which is cost (estimated to add roughly $30 - materials and labor - per 4' X 8' sheet of drywall to an installation) and, secondly, the far too frequent performance failure of RC due to tricky installations that are notoriously done wrong. For this reason, many acoustical consultants won't recommend RC as a sound dampening solution.
SureWalls Is The Sure Way to Defeat Sound Transmission - SureWalls beats sound transmission by permitting the installation of drywall with very few mechanical connections of the drywall to the underlying stud framing. It decouples the drywall panel from the stud wall as effectively as RC - in those cases when an RC installation is carried out to perfection. In both cases (RC and SureWalls) you can expect an increase in the wall's STC performance in a 5 to 10 point range which is highly significant. But, SureWalls has a few huge advantages over RC. Most importantly, you simply can't get the installation wrong with SureWalls. The system provides for a straight-forward, error-free installation that requires none of the additional or tricky steps required of an RC installation. Second, when you install drywall with SureWalls you aren't adding another step to drywall installation. SureWalls is your one and only installation step. Once drywall is installed with SureWalls it's ready for finishing, no additional labor or materials required. In fact, from that point on the labor needs are considerably less than what's required for a standard or traditional installation. This means that the overall cost of drywall installation (considering the substantial savings in labor) won't be greater with SureWalls than if you have performed an old-school "screws, tape and mud" installation. Finally, with RC walls, it's highly recommended that no cabinetry, heavy shelving or even TV monitors be attached to the wall due to the wall's inability to perform with the added weight. There is no such limitation with SureWalls. As long as an installed cabinet or shelf does not make a mechanical connection to a stud, the system will retain its full sound dampening quality as well as being plenty strong enough to support the added weight.