How to Soundproof Ventilation

Air vents are a necessity for any house. It allows airflow to pass throughout the house which in return helps to extract moisture from your home preventing moist buildup within the exterior walls. The downside of air vents is it allows for exterior sounds to pass-through the vents and entering your home. With this in mind, you are probably looking for simple but practical ways on how to soundproof the ventilation of your home without spending a small fortune. For me to guide you in the best possible direction you need also to consider other ways to reduce external sounds from entering your home like how to soundproof certain areas in your home like your office and the best types of insulation for interior walls.

How to Soundproof Ventilation

With the right tools, soundproofing can be done under 15 minutes and if done properly you can have soundproof ventilation with air vents that allow for air to flow into your home. So let’s have a look on how to soundproof ventilation.

5 Best Ways on How to Soundproof Ventilation

Method 1

Block the Vent

This is by far the easiest and cheapest way to block exterior sounds from entering the air vents. To do this you will need a type of sealant to help you achieve the desired outcome. We recommend Great Stuff 157906 Insulating Foam Sealant. This sealant expands when spraying and forms a layer of foam-forming an airtight water-resistant seal while reducing external noises from entering the ventilation.

Great Stuff 157906 Insulating Foam Sealant

Method 2

Create a Sound Maze in the Air Vents

Another cheap and easy way on how to soundproof ventilation is to create a sound maze in the air vents that you want to block off. This particular method involves some supplies that you already may have in your storeroom or you can get it for cheap at your local store.

  • Thin plywood
  • A screwdriver
  • Wood glue
  • A wood saw
  • A utility knife
  • Acoustic foam material

Step 1 - Use the wood saw to cut the plywood into small pieces to fit into the air vents. Cutting these pieces to big can lead to blocking the airway. The more pieces of squares you cut the better the outcome will be.

Step 2 - Involves covering the wooden pieces with acoustic foam material. Spread n thin layer of wood glue on the wooden pieces then apply the foam material on the pieces of wood. The acoustic foam attached to the pieces of wood will provide an extra layer of soundproofing in the air vents.

Step 3 - Remove the vent covers with the screwdriver.

Step 4 - Next, you need to attach the wood pieces to the sides of the wall using the wood glue. Repeat this step with each wood piece until finished. I recommend that you leave approximately 1inch of space between each piece for air to circulate.

Method 3

How to Block Rattling Sounds from Air Vents

Rattling sounds from air vents can be extremely irritating especially at night when you get ready for bed. These sounds can generate from your HVAC system which blows compressed air down the pipes and through the air vents. This could be an indicator that your HVAC system is getting old and replacing it can be expensive. The simple solution to dampen the ratting sounds generated from your HVAC is to invest in a soundproof blanket.

A soundproof blanket reduces the compresses noise up to 40% and fits most HVAC models.

Method 4

Install a Sound Baffle

A sound baffle is a box that forces the sound to travel longer distances within a particular space or path. This method can be tricky but effective if done correctly. The box is lined with sound-absorbing materials on the inner walls. These materials dampen the sound moving from one point to another until it disappears when reaching the outer vent. For the best outcome, I suggest placing flex duck tape along the curved path and then sealing the box.

Flex Duck Tape

This method works great when you’ve already installed an HVAC, but will not be as effective when you want to soundproof normal air vents in your house.

Method 5

Using Soundproofing Curtains or Blankets

This is not the most effective way on how to soundproof ventilation but should help to reduce acoustic sounds from entering the room. With the use of heavy soundproof curtains which is placed over the ventilation areas, this technique is cost-effective and easy to install. After all, you will be able to remove and install them as often as you like without spending money continuously.

Our Recommendation


To properly soundproof the ventilation we suggest that you look at methods 1 and 2 which is by far the cheapest and most effective way of soundproofing your ventilation. While method one is affordable you need to understand that the foam will crack after some time and then you need to redo the whole process over. Method 2 can be considered a bit of labor-intensive but this technique is useful in the sense that it controls both noise and air circulation.

Final Thoughts

As mentioned before soundproofing your home needs careful planning and some investment, but with the right materials, you can reduce acoustic sound from entering your home up to a bare minimum.

This guide on how to soundproof ventilation gives you the tips to finish your project accordingly. Based on my experience and advice from experts on AVSforum and other industries soundproofing is not a quick fix solution but will tremendously help to reduce external sounds from entering your room whether it is through the ceiling, walls or vents.


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