Soundproofing a Room

Beth Asaff
Acoustic foam

There are many different reasons why homeowners may want to soundproof a room. From reducing noise around bedrooms to sealing off a recreation room for the kids, learn the basics of soundproofing a room to ensure it gets done right.

Soundproofing Basics

Before you begin construction or demolition on your soon-to-be soundproofed room, here are few basics about walls, insulation and noise level.

Sound Transmission Class Ratings

Sound transmission class ratings, or STC ratings, are measurements of how well a structure insulates against noise from either inside the room or outside the room. The basics for STC ratings are simple - the higher an STC rating, the more soundproof.

For example, gypsum board, commonly referred to as drywall, is a relatively decent soundproofing material. A single layer of gypsum attached to two-by-four inch studs has an STC rating of about 36. At this rating, loud conversations can be heard but not understood and shouting can definitely be heard and understood.

Making Walls More Soundproof

If you don't want the mess and aggravation of a huge demolition project, you can easily increase the sound-blocking quality of an existing wall by adding another layer of gypsum board on top of the existing layer. If you have a little more time, skill and patience, there are more involved things you can do to dramatically increase the soundproofing of a room.

Adding More Layers

Soundproofing insulation

Again, if you don't want to tear down your walls and start over from scratch, you can improve the STC rating of a room by simply doubling the studs and then adding another layer of gypsum board. Be aware, though, this will cause the room to be just a bit smaller in the end. Here's how to do it:

  1. Locate the existing studs. Once you find and mark them, build a new stud frame according to your measurements.
  2. Attach the new frame to the existing studs, being sure to attach it at the floor and the ceiling joists as well.
  3. Add a thin layer of insulation in between the two layers of walls.
  4. Then, install an additional layer of gypsum board.

Building an additional layer on top of the existing drywall should increase the STC rating from around 34 to between 40 and 45. This difference may seem small, but it is very noticeable when it comes to noise.

Tearing the Walls Down to Studs

soundproofing with insulation

Tearing down your existing walls to studs takes a lot more skill, patience and effort, but doing so increases the STC rating of a wall dramatically. Here are the basics:

  1. Remove the old drywall. Once you have the old drywall torn down, nail new studs to the existing studs.
  2. Add Batt insulation. This is your typical fiberglass insulation sold at any home improvement store.
  3. Install new gypsum board.

By doubling the studs, adding the Batt insulation and then installing a new layer of drywall, you will improve the STC rating of your room to around 60 as opposed to the single layer STC rating of around 34.

Using Soundproofing Products

If you have a bit of breathing room in your budget, consider using some of the following products when soundproofing a room.

Barriers

These specially designed barriers are made to absorb noise and vibrations. They are soft, made of a combination of foam and soundproofing composites reinforced by Mylar. They are generally pretty thin, around two inches thick, and have a peel-and-stick backing, making them easy to install. These barriers are perfect for using in a utility room or closet that contains your H.V.A.C. system. Just apply them to the walls and the back of the door to help deaden the sound within.

Where to Buy

You can purchase barriers from:

Soundproofing Drywall

Whole wall soundproofing systems are designed for use in new construction and existing walls. These systems consist of special types of drywall that absorb and block sounds; the drywall is plastered and painted like a normal wall, giving you a soundproof room that does not look any different than a standard room.

Where to Buy

Get soundproofing drywall from Quiet Rock.

Acoustic Panels

Fabric panels

These panels are designed to absorb sound and come in a variety of different colors. The panels can be installed on walls or ceilings and there are several different types available. Some options include:

  • Fabric covered panels: Cloth-wrapped panels with a perforated membrane below the cloth that diffuses sounds
  • Barrel diffusers: Large, rounded panels typically used in large areas for a vertical presentation
  • Pyramidal: Large, pyramid-shaped wall panels that break up and diffuse sounds inside the rooms
  • Ceiling clouds: Fabric panels that are suspended from the ceiling to help block additional sound

Where to Buy

Get acoustic panels from:

Deaden Sound Effectively

The amount of soundproofing you will want to add to a room depends on what it is you want to accomplish. Creating a more quiet sleep environment may require less soundproofing material than creating an acoustic chamber will. Use a variety of soundproofing techniques together to create just the environment you desire.

Soundproofing a Room