A finished basement is a valuable asset to a household, providing functional space for a family and potentially adding value to the home. Basements can be quite large in many homes, affording homeowners the option to personalize the space for a wide range of purposes. Possibilities abound for converting the basement of a home; they often serve as family rooms, home theaters, recreation rooms, offices, even additional bedrooms.
Left untreated for sound transmission, the walls and ceiling of a basement will serve as mediums through which structural sound vibrations are delivered throughout other parts of the home. Additionally, sounds originating within the room, from sources such as a home theater or people conversing, will reverberate from surrounding wall and ceiling surfaces, interfering with the intended sound and diminishing the quality of acoustics within the room. Both sound transmission and sound reverberation are natural sound wave behaviors which should be targeted in comprehensive basement soundproofing project.
The goal in controlling sound transmission is to isolate the basement such that its ability to conduct vibration is compromised. This is accomplished in part by increasing density and establishing a disconnected wall surface that will serve to collapse sound waves rather than deliver them structurally throughout the home. Treatments for unfinished versus finished walls vary slightly, but are aimed at the same sound behavior and thus utilize similar methods.
The treatment of a basement lined with exposed studs not yet fitted with drywall should begin before the wall is constructed. Applying the density + disconnect configuration in this case involves first applying a heavyweight vinyl soundproofing membrane such as dB-Bloc to the existing studs, taking care to cover the entire wall surface. This technique fulfills the first objective of the project—adding density. Next, a separated wall surface should be constructed through the application of a new layer of drywall affixed to a set of horizontal furring strips that have been secured atop the vinyl layer. The space created within the wall assembly causes sound waves to collapse rather than traveling directly through the studs and into other parts of the home. Though it is only necessary to treat one side of the exposed frame, exterior foundation walls of a basement may also need to be treated for optimal results.
It is not necessary to deconstruct finished walls and expose the frame in order to apply soundproofing treatments. A finished wall can be covered with a layer of heavyweight soundproofing vinyl, forming the foundation for the framing technique and additional drywall layer as described for the treatment of an unfinished wall.
Controlling sound transmission from a basement necessitates that the ceiling be treated in addition to the walls. The appropriate ceiling soundproofing treatment is dependent on the unique characteristics of the basement being treated. For instance, specialized soundproofing panels and caps are available for the grid type ceilings common in basements. Alternatively, finished or unfinished ceilings can be outfitted with a separated surface, similar to the way a secondary wall surface is created as described above.