Soundproofing a Garage - Layer of mass loaded vinyl, double leg resilient hat channel and layer of drywall. For this project, we are soundproofing a garage to create a music rehearsal space.  We converted a 20’x 20′ garage into two L-shaped spaces. The front portion of the space with the garage doors is a workshop and the other half is a music rehearsal / recording space. The rehearsal space requires soundproofing to avoid disturbing nearby neighbors.

Typical Tools Needed for Installation:

T tools ape measure | Hammer | Metal straight edge | Utility knife | Staple Gun | Hack Saw | Protective safety gear.

Other tools may be required to install subsequent layers of materials.

Site Preparation

Before starting, be sure to clean & organize your space. Starting with a clean organized space is always a good way to begin any construction project. Since garages are typically unfinished spaces, we will begin with the bare stud structure of the room. This is a good time to mark stud locations on the floor. This will be beneficial later when adding the multiple layers of materials.  It will make finding you studs a cinch.

There are many variations of wall assemblies that can be constructed to block sound. For this project, the home owner and I discussed several options. Considering the space limitations and overall objectives, we chose to install a layer of AudioSeal Sound Barrier, followed by a resilient channel and 5/8″ gypsum.

Install Insulation

Soundproofing a Garage - Be sure to insulate the structure of the building. This will help all to the overall STC rating of the structure.

Soundproofing a Garage – Be sure to insulate the structure of the building. This will help all to the overall STC rating of the structure.

Install standard insulation in the stud cavities. This will not only provide an “R” value, it keeps the cavities from resonating sound. This will help to increase the STC (Sound Transmission Loss) of the wall assembly by approximately 4-6 dB. Feel free to use any type of insulation. There are many types available including standard wall insulation, mineral wool, cellulose, etc. For this project we elected for basic R-13, 3’1/2 thick, paper faced insulation.

Before you start installing the insulation, be sure to be wearing protective gear including work gloves, a mask and eye protection. Fiberglass particles can be hazardous if inhaled or if they get into your eyes. You simply roll out the fiberglass, take your utility knife,  and cut the paper facing and the fiberglass to length and stuff it between the studs. There are paper tabs on the edges that you pull out and staple to the studs. We are saving our scrap pieces to fill odd sized cavities and sliver spaces. The rolls can be cut by using a metal straight edge and a utility knife.

Caulking the Stud Structure

When soundproofing a room, be sure that you seal all seams and gaps. If air or light can pass through your wall construction, SO CAN SOUND!

You will want to use a caulk specifically meant to block the sound. Ohio Sealants make an acoustical sound caulk. Pro Series OSI® SC-175 comes in a 28 oz. tube that contains approximately 40 linear feet of caulk.  You will need a larger caulking gun as these tubes are larger than the traditional caulk or adhesive.

Before applying your sound caulk, be sure to clean the areas from dirt.

We are sealing the tops of our wall cavities where the meet the roof and the studs where they meet the floor.

Simply follow the instructions on the tube of caulk. Cut the tip of the tube to the desired size to achieve the appropriate bead size. Squeeze the caulk from the tube to get a continuous smooth bead of caulk. Once the caulk is applied, smooth with your finger or a caulking tool.

NOTE: If the walls will have electrical outlets and switches, now would be a good time to seal the gang boxes with something like putty pads. For this application, the electrical will all be surface mounted to the finished wall.

Installing the AudioSeal® Sound Barrier

Soundproofing a Garage - Four 30' Rolls of barrier ready to install. The four 30′ rolls of AudioSeal® Sound Barrier were off loaded from the truck. We have chosen to use this particular material because it is only 1/8″ thick. This will save us space in the construction of the walls as well as providing a layer of material that has a different thickness. This limp mass material is impregnated with barium sulfate to add mass, which is what helps block the sound. It weighs one pound per square foot, as heavy as lead. Also, by have materials of different thicknesses the sound had to change its speed in order to pass through the material, therefore slowing it down. These rolls are very heavy so be sure to have help or proper equipment to move them around.

We will be installing the sound barrier horizontally instead of vertically. We have chosen to do this so that we can hopefully have fewer seams to seal. To accomplish this we will need a structure to tack the barrier to about halfway up the wall. We purchased some regular framing 2 x 4s to cut and install between the existing studs to create a tack strip around the room.

The next step is to roll out the sound barrier and cut to size required. Simply roll out the material to the desired length. Then cut the barrier using a utility knife and straight edge.

Take the cut piece and install it on top of the studs. Here we used roofing nails to hold the barrier in place. The large nail head provides a good amount of surface area to help support the weight of the sound barrier while under construction. 

Seal any Seams and Gaps with Acoustical Caulk

Once the barrier has been installed to the studs, caulk all seams and gaps with an acoustical sealant.  If light or air can pass through the assembly, SO CAN SOUND!

Install resilient channel & drywall

The next step was to install the resilient channel. We purchased a double leg hat channel from a local contractor supply company. These can be cut to size using a metal hack saw. Finish drywall as necessary.  Seal any seams or gaps with acoustical caulk. Depending on how far you want to take your build out, you can also add isolation clips and Green Glue between additional layers of drywall.

The ceiling of this room was done in standard drywall to the ceiling framing. The back will be lined with insulation and a layer of AudioSeal Sound Barrier may be added at a later date.

The interior of the space has acoustical panels, diffusers and some acoustical foam behind some curtains. Some of this may be covered in a later post.