In today’s competitive rental market, apartment soundproofing plays a key role in besting the competition. As the privacy of tenants who live in a multi-dwelling unit is disrupted, the issue of noise pollution becomes a problem for apartment owners. Common wall soundproofing is an essential step in protecting tenants from noisy neighbors. Without apartment soundproofing, the noise will drive tenants out.
The Issue: How Sound Transfers
The key to combating sound bleed through common walls is to first understand how the energy is transferring. Most common walls are not designed for sound abatement. They are built with a single frame, drywall and batting insulation that is stuffed into the cavity spaces. The frame becomes the focal point for the energy transfer, much like a string pulled tight between two cans.
Note that the sound panels on the market are not designed for sound isolation. Sound panels absorb echoes within a room, such as a loud restaurant, but do not serve to block the noise that transfers from room to room.
The Solution: Density & Disconnection
The first step is to add density to your existing surface. In order to combat noisy neighbors, the soundproofing technique is to first anchor mass loaded vinyl to the existing surface. Be careful to tear nothing out; just layer it right on the drywall.
The second step is to disconnect the framing, forcing the collapse of the transmitting vibration. This is accomplished with a simple set of resilient channels or isolation clips, which can be added to the existing finished wall and followed up with a new layer of 5/8” drywall.
The channels and drywall can be easily sourced in your local market, while the mass loaded vinyl is drop shipped to your project site in the form of a product called dB-Bloc. Note that if the common walls between living spaces are already a double wall, you already have the disconnection you need, and you can forego the channel system. However, you will still need to add the density that your current wall assembly lacks.
This technique can keep up to 90% of the transmitting noise from bleeding through apartment walls.
You can apply this layering technique to your existing wall before the next tenant moves in. The key is to stay proactive with soundproofing treatments as each unit becomes available until all your units have been retrofitted over time.
Sound Transmission Classification for Common Walls
In the world of acoustics, you can measure a common wall’s ability to hold noise through a Sound Transmission Classification (STC). A standard studded wall that has batting insulation between the studs and a single layer of drywall on both sides will deliver an average STC rating of 38-40. On the STC scale, this is pretty weak. Government standards for a luxury grade rating will deliver STC ratings of 55+. The layering technique described here is designed to lift your existing wall to the luxury grade STC rating.
For more information on protecting tenants from noisy neighbors, go to our Wall Soundproofing section. By using the layering system mentioned in this blog — adding density and disconnection to your common surface — you’ll enjoy a luxury grade wall system. Your tenants will thank you.
