How to Soundproof Your Basement?

Most homeowners do not see the need to soundproof their basement since the space is one of the least visited places in a home. However, things can change radically if you rent out your basement to tenants or convert it to an office or study. In these instances, soundproofing your basement becomes not just important but necessary.

Soundproofing your basement will also help you arrive at a solution where you don’t inconvenience your tenants with all that impact noise or get inconvenienced by the noise from their blaring TVs—win-win for everyone.

Before exploring the subject fully, let’s understand how noise gets transferred from room to room in a home.


How Does Noise Get Transferred to And from the Basement?

When you identify the methods through which sounds get in and out of your basement, it’ll be much easier to concentrate your efforts towards plugging the gaps. The two kinds of noise you’ll be looking to control are airborne noise and impact noise.

Both noises travel in different ways, although some types of noise can be categorized under either of them. Think of a subwoofer blasting loud music while still creating bass vibrations.

Airborne Noise

Airborne noise, quite simply, is the noise that carries through the air. It’s the most common type of noise in a home, generated by multimedia gadgets, parents conversing, kids playing video games, and pets barking. Airborne noise travels through open spaces, doorways, and open windows.

These types of noises can be more easily controlled and prevented from permeating into an airtight basement by sealing the main entry point – the door.

Impact Noise

Impact noise is generated when an airborne sound wave hits a solid structure, becomes a vibration and travels through barriers such as walls, floors, roofs, and ceilings.

The term implies that the noise is generated by the impact of two materials hitting each other such as feet pounding stairs or floors, balls bouncing off walls, and objects clattering against the ground.

Impact noise can be controlled by reducing or eliminating the points of contact between a structure’s parts.

Remember that for soundproofing to be effective; you must interrupt the ways through which sound travels to and from your basement. That’s what we’ll be considering next.


Elements of Soundproofing

These are the four methods you can use to soundproof your basement ceiling. For greater effect, all four can be used together:

  • Decoupling: This method effectively breaks the sound wave vibration path. It involves separating ceiling levels by creating a gap between the joists and ceiling layers. It’s the most effective soundproofing solution.
  • Adding Mass: By adding mass to your ceiling composition, you’re making it more difficult for sound to vibrate through. However, you’ll need to add a lot of mass to reduce enough vibrations to make a difference.
  • Damping: This is the method of using viscoelastic compounds to reduce sound vibration in ceiling joists and wall studs.
  • Absorbing: Absorbing involves the use of dense materials to absorb sounds.


How to Soundproof Your Basement Ceiling?

Depending on the state of completion of your basement ceiling, there are a few options available to you. Ceilings with exposed joists and ductwork are easier to soundproof because you won’t have to drill through or remove your drywall.

We’ll start with how to soundproof an exposed basement ceiling.

1.     Insulate the Joist Cavities

You’ll normally see empty wooden joists in the ceilings of unfinished basements. To minimize noise transfer from upper-level rooms, those cavities will need to be filled up.

The best acoustic insulation is the Roxul Safe’n’Sound insulation, which is a stone wool insulation product that can reduce noise and sound absorption in residential wood and steel stud construction.

  1.   Install Resilient Sound Isolation Clips

The goal of sound isolation clips is to insulate the wall studs as much as possible. These clips are attached to wall studs and then used to help with screwing into drywall.

Sound isolation clips do not conduct sound, as they usually consist of some type of rubber. These isolation clips are used for vibration control of structure-borne noise and help build assemblies that will more effectively block airborne noise transmission.

3.       Install Resilient Channels Across the Joists

After you’ve filled the joists with insulation, the next step is to install resilient channels across them.

The metal railings will act as a flexible buffer between the timber beams that form your home’s foundation and the drywall that will be installed next; this effectively decouples the two surfaces, preventing impact noise from being transferred between them.

4.       Install Your Drywall (5/8 type x)

Once you’ve completed setting up your network of resilient channels, you’ll need to switch focus to screwing on your drywall. This part is a bit technical and requires patience and care, so you don’t end up inserting the screws in the wrong places.

Ensure that you drill your screws through the resilient channels, not the joists.

5.      Install Another Layer of Drywall, Smear with Green Glue And Add It to The First

Green Glue is not just glue; it helps minimize the sound impact by turning sound waves into heat on contact. To be effective, you’ll need to stick it between two firm surfaces, hence the need for the drywalls.

Cover a sheet of drywall completely with Green Glue, then lift it to the already installed drywall and hold it in place until both sheets merge.

6.     Plug the Gaps

Before you put in the finishing touches, you’ll have to block all possible gaps, so that airborne noise don’t find their way into and out of your basement. Use acoustic sealants to block all loopholes.


Extra Noise Reduction in Your Main Floor

After you finish soundproofing your basement’s ceiling you can add another layer of noise reduction by enhancing the soundproofing from above. You can do this through any of the following ways:

  • Cover the floor above the basement ceiling with thick carpets or rugs
  • Place furniture over the basement ceiling weak spots
  • Install acoustical ceiling tiles
  • Put mass-loaded vinyl under the carpets on the floor above the basement.

This article contains just a few of the steps that are required to effectively soundproof your basement. For best results it is recommended that you contact a professional soundproofing contractor.