How to soundproof air vents: 3 Easy methods that work
I have a nice office at home. It’s the right size and has all the materials I need to work without a long commute. However, if my spouse was cooking, I could hear the loud appliances through the air vent, which led me to thinking how to soundproof air vents.
If my son was playing the drums or doing woodworking in the garage—same problem. I am not very handy and do not enjoy working on the house. I had no desire to wear headphones or anything else.
For a short time, I considered returning to the office in order to have quiet while working and on conference calls.
But then I learned you can actually soundproof an air vent itself. I was not sure if I wanted to block off the vent—and risk losing the heating and cooling—or if there were other options.
It turns out there are several strategies you can use to quiet your air vent.
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Contents: Skip to section
- How to soundproof air vents: 3 Easy methods that work
- Types of noise
- Who is this for and why is this article helpful?
- What are my options? Recommended Gear
- Sound maze
- Sealing Off a Vent
- Cover the Air Vent
- Frequently Asked Questions (FAQ)
- How to soundproof air vents: Conclusion
Types of noise
There are two types of sounds that pass through your house.
Airborne is the type of noise that passes through the air: music, television, conversation, anything of that sort.
If you are getting sounds through your air vent of this type, then you have quite a few options.
Structural or impact noise is the type of noise that results from people walking around or bumping into things. This travels through the frame of the house and that’s a topic you can find in other articles in this blog.
Just keep this in mind when you decide if working on your air vent is a good option for you.
Who is this for and why is this article helpful?
If you have a home or apartment and are getting noise through your air vent that you want to cut down on, then this article is for you.
If you are willing to purchase a few simple items and employ a few simple strategies, you can make a big difference.
At first, I was worried I would need to block the air vent. I had visions of closing it off completing and being stuck in a room that was always too hot or too cold.
Then the more research I did, the more I realized I could, indeed, keep the air flowing while cutting back on the noise.
The noise coming through the air vent might be enough to disturb your sleep or work.
But a little bit of effort can fix the noise interfering with your sleep and work.
What are my options? Recommended Gear
Aside from permanently sealing up the air vent permanently what are the options?
- A sound maze, which will absorb sound and bounce waves away from your direction
- Insulating Sealant
- Acoustic foam in or over the vent
- Soundproof blankets
Probably the best way to soundproof an air vent by creating what is typically called a sound maze inside your air vent and duct.
It will definitely cut down on the noise coming through your vent, but will not block airflow, a critical balance to strike in this type of project.
To do this you will make mini-sound barriers that will go in the duct, which will absorb sound, but leave a gap for the air to flow through.
The materials recommended below will help bounce sound back from passing into your room from another source and will deaden the sound before it gets to you.
When you add these items, the air itself will flow in a zig-zag motion through the maze, but the sound will eventually dissipate before reaching you.
Tools you need:
- Acoustic foam
- A Step Ladder
- Green Glue or Gorilla Wood Glue
- Utility Knife
- Wood Saw
This is another multi-tool driver, with nine screwdriver bits and nut drivers. The Klein is a standard workhorse tool, whereas this Irwin focuses a little more on design.
The bits are stored in the handle for extreme convenience anytime you need to change them.
The handle is ergonomic and designed specifically for slip resistance, making for comfortable safe usage.
Steps to build your sound maze
- Shut off your HVAC system (or wait until you’re ready to install the maze).
- Using the stepladder and screwdriver, remove the air vent cover.
- Measure how far back into the vent you are comfortable placing the maze walls. Remember you will need to hold it in place for a few minutes while the glue dries.
- Measure the height and width of the vent.
- You will want to keep the maze walls 1-2 inches apart from each other. Determine how many of the walls you will need, keeping in mind you will place them in a zig-zag fashion, alternating between the left and right side of the duct maze. They should be as tall as your airduct and roughly two-thirds the width.
- Using your tools, cut the plywood into pieces.
- Now cut the foam panels into matching pieces and glue them to the plywood.
- When the glue is dry you can begin installation.
- Place the pieces as far back as you feel comfortable, adding glue to them on three sides and holding them in place until they dry and can stand on their own. Continue in an alternating pattern.
- Wait the designed time on the glue container to ensure the glue is fully dry—you do not want to breath in glue fumes. Once it is dry, turn the HVAC back on and ensure the glue and placement has worked.
- Replace the vent.
Sealing Off a Vent
If the above is too much to try right now, there are other, easier methods.
Try using a Soundproofing Sealant.
If the HVAC vent is not active, or you do not need the airflow from it, you can seal it off. There are several options for this but the easiest one to use is the insulating foam sealant. Foam sealant will expand to fill the air vent.
Using Insulating Foam
- Turn off your HVAC system.
- Remove the air vent cover.
- Reach in and spray the foam sealant into the duct. Keep in mind it will expand, so unless you want it to be visible, reach back into the vent and apply the sealant.
- Once you have filled a section, and the sealant has set, it will be airtight and relatively soundproof.
- Be sure the sealant is fully dry, then you can replace the vent.
- Turn on HVAC system to test.
Cover the Air Vent
You can temporarily cover the vent itself with one of several items.
You can install any number of soundproof blankets with nails, hooks, or other hanging tools. You have two options with this: you can cut the blanket to fit over the vent or you cant stuff the blanket inside the vent. If you go with the later, just ensure you bunch it up enough to fill up the space tightly. It will not be as effective as other methods, but it will make a difference.
Even if you do not want to make a full-blown sound maze, you can put your acoustic foam panels to good use. Cut them to the size of your air vents and glue them to the back (inside) of the air vents.
This will not cut down on sound as much as the maze, but will dampen the noise. (See acoustic foam panels above in the maze instructions for product selection.)
If you do not want a blanket or acoustic panel hanging over your vent, you can also consider a decorative acoustic wall panel, which has the added benefit of being aesthetically pleasing.
Frequently Asked Questions (FAQ)
Is it OK to cover my air vents?
Industry experts indicate that covering your air vents may impact your HVAC efficiency. The primary safety concern is whether your home may have asbestos or not. If it is relatively old, it could.
Blocking the vent can potentially cause air flow buildup which may dislodge particles. Aside from that, the main concern is a potential drop in efficiency.
For these reasons, this article provides solutions other than simply covering or blocking your vent. If you’re concerned about any of this, consult an HVAC technician first.
To soundproof my air vents do I need to cover them and block air flow?
No, there are several options available to you. The best option is a sound maze, which does not cover or block the air flow at all. It absorbs and deflects the sound, but does not impeded air flow.
Do I need an HVAC technician to soundproof my air vents?
No. While it may be a good idea to consult one initially about any concerns related to your HVAC system, all soundproofing of air vents can be accomplished with a few simple tools and materials.
Even the most complex solution discussed here only requires a few materials and a saw and glue.
How to soundproof air vents: Conclusion
There are a number of strategies to choose from here.
The best in terms of soundproofing and airflow is clearly the sound maze.
It is not too hard to create and but it makes a significant difference.
Be sure to click through to find out more about the products and choose the one that suits your needs the most.
Good luck with your soundproofing project!