Window air conditioners are portable, easy to set up, and affordable. They are the most efficient air conditioners money can buy for their size, but they are not without drawbacks.
Sometimes window air conditioners can be extremely loud, which can disrupt your sleep and disturb your neighbors.
Faulty window air conditioner installation can also let ambient noise, road noise, and other outdoor unwanted sounds into your beloved home.
If a situation with a loud window air conditioner isn’t handled right, an obnoxiously loud window AC can lead to confrontations with neighbors.
Can you actually soundproof the window air conditioner and keep all types of noise pollution at bay?
You absolutely can.
This post will teach you exactly how to soundproof a window air conditioner from external and internal sounds. You will learn the best way to reduce outside noise from a window AC from installation and beyond.
What Kind of Noise Pollution Are You Dealing With?
Noise pollution depends on several factors. The most important factor is whether the AC was correctly installed.
Sounds Due to Inept Installation
Inept AC window installations occur all the time. The AC may not be perfectly flush with your walls, and the inserts used to seal the space may not meet the AC in the right place. It is even possible for the AC to be the wrong size for the window.
Poor installations lead to open gaps that allow sound waves to enter your room.
Sometimes, when the AC is not tightly secured, vibrations can start to rattle surrounding components, leading to increasingly unpleasant sounds. Loose screws, dripping water, and transmitted vibrations are prime examples.
This is also an example of impact sound that you want to avoid when soundproofing a window AC.
Window Air Conditioner Sounds
Window air conditioner sounds are the other type of noise pollution you could be dealing with. This kind of disturbance usually denotes an underlying problem from the AC and may sometimes be related to the air conditioner's age. Naturally, as ACs get older, they tend to get louder if they aren’t properly maintained.
If your Window AC was installed properly and is not making any funny sounds, your main issue might be transmitted sound coming from the outdoors.
If this is the case, you typically won’t have to take any action because the sound transmitted through your glass will likely not cause a nuisance.
On the other hand, if you work from home, produce video or audio content, or have a home studio, recorded media will be affected as your equipment will pick these sounds up as distortions.
If this is the case, you still have to soundproof your window air conditioner for the best results.
How do I Reduce Outside Noise From a Window Air Conditioner?
Window ACs are portable and affordable, but they usually aren’t installed tightly enough. Small gaps and spaces around the window AC let noise and warm air in and cold air out, reducing the effectiveness of the AC.
For most homeowners, the solution to this problem might be as straightforward for most homes as sealing the gaps with insulation. Let’s explore all the possible solutions if you are trying to eliminate outside noise.
Use Fitted Insulation to Seal Gaps
For best results, use rolled fiberglass insulation to cover gaps and spaces that let in noise. It should fully cover all openings around the window air conditioner, soundproofing it from outside noise.
If you are dealing with a larger window, measure the open space, go to your local hardware store, cut the exact shape of the area out of a block of insulation, and use it to seal the gap.
Use A Custom AC Enclosure
If you want something more visually appealing, use a custom-made AC enclosure to seal any open space you may have around your unit. This will also reduce noise pollution and keep the areas around your window AC clean and free from dirt.
Most enclosures are made from plywood and Formica and can be finished with a color that will match your home.
Use Silicon-Based or Latex Adhesive
If the spaces around the edges of your window and the window frame are small, you can use silicon-based adhesive (caulk) to quickly and easily seal up the holes.
Caulk is very effective and flexible, so it will remain in place regardless of the temperature changes from the air conditioner.
Make sure you clean the area before caulking and use your hand to smooth out the caulk after applying it before it dries out completely.
How To Soundproof Window Air Conditioner
Usually, the frustrating sounds that come along with having a window AC will come from the AC itself.
Before you decide to entirely replace your unit, if your AC is still functional, you could soundproof it and reduce the noise altogether.
To make the decision on what to do easier, we have listed our best recommendations below according to the kind of sound your AC is making.
Check For Loose Parts
Before you proceed with other soundproofing methods here, check for loose parts.
If you've been using your window for a few years, there is a slight chance that some parts have become loose, resulting in the unusual sound your AC is making.
First, turn your AC off and check the frame of the AC, the fan, and the screws that hold several pieces in place. If you come across any loose parts or screws, fix them back in place and test the AC to see if it is still loud when it runs.
Consider Using Soundproof Blankets
Compressors are the most common cause of window AC noise, so if you happen to hear a combination of sounds from time to time as your AC gets older, the compressor is the likely culprit.
If your Window AC makes popping and rattling sounds, or even a shrieking noise, the compressor is the most likely cause. The quickest way to dampen compressor noise is to use soundproof blankets.
A soundproof compressor blanket will block most of the sounds coming from the compressor and will save you the cost of having to replace the compressor or the AC.
Additionally, most compressor blankets are universal in size, designed to fit most compressors regardless of AC brand.
Surround the AC With an Acoustic Sound Barrier
Sound barriers can be effective for controlling how loud the AC generally is. If the sound from your window AC is causing frustration for both you and your neighbor, an acoustic sound barrier can easily resolve the solution.
Sound is transmitted as waves, so an acoustic sound barrier/absorber around the AC can capture and absorb from 10 to 40 dB of the sound.
When installing a sound barrier, always leave some space between the AC and the border to ensure proper airflow and avoid overheating. It should be noted that soundproof blankets are more effective when dampening localized sound.
Repair/ Replace Faulty Parts of Your Window AC
Some parts of the AC, like the fan, the compressor, and the hoses, can lead to unusual sounds if damaged.
Something is obviously wrong if your window AC suddenly starts making popping noises or clicking noises. The electrical wiring could be short-circuiting when you hear clicking sounds, or the compressor could be overloaded with the refrigerant. A damaged fan can also lead to incredibly loud vibrating sounds.
The best response in this situation is to immediately turn off the AC and contact a professional AC technician to troubleshoot and repair the AC. Professional repair or replacement of faulty parts can renew your window AC and eliminate any weird sounds it might be making.
How To Soundproof Transmitted Sound?
Sound can travel through solid glass and wooden frames of windows. No matter how tightly fitted your window AC is, sound waves traveling in the air are transmitted through the glass as vibrational waves.
As a result, you can still pick up some sounds through a shut window, but sounds transmitted through the vibrations of the glass are barely noticeable and are considered okay for many homes with infrequent sound disturbances.
On the other hand, if you want to keep all sound out and limit the sound transmission out of the room, you need a fully soundproof window air conditioner.
Make Use of a Custom Window Insert
Window inserts have excellent soundproofing qualities and can reduce up to 70 dB of sound transmitted through glass and window frames.
They are made of acrylic material and have acoustic tubing on the sides to ensure there are no escape routes for transmitted sound.
Installing a custom window insert is a straightforward process, but you may need to contact a recognized manufacturer of window inserts rated to reduce up to 70dB of outdoor sound.
The company will either send out a technician to take an appropriate measurement of your window or send out a measurement kit to take the measurements of the window frame. The required dimensions will differ depending on where your window AC is installed and how you want to decorate the window.
Soundproof Doors and Windows
Another viable option is to soundproof the windows and glass doors with acoustic foam panels or Rockwool to absorb transmitted sound and reduce sound reflections from the room.
The only downside to this method is losing the natural light transmitted through the glass because the panes block out the window. Still, it might be worth it to you to get a fully treated room that is entirely soundproof from window air conditioner noise and any outdoor noise.
Use A Combination of Acoustic Window Blinds and Curtains
If you want to retain natural light and the ability to open the windows whenever you want, one option to consider is acoustic-grade curtains and blinds.
Acoustic window blinds will reflect the transmitted sound, and sound-absorbing curtains will absorb much of the sound transmitted.
Although these options are not as effective as window inserts, they can further reduce sound transmitted as vibrations through the glass.
Tips for Installing a Window Air Conditioner
Installing a window AC correctly is one of the best ways to prevent unwanted sounds from traveling into your home. Pay close attention to the following tips when deciding to install a window air conditioner.
Use a Window AC Rated for Quiet Operation
Newer AC models are superior in every way to their older counterparts. They consume less electricity, cool faster, and operate with less noise. Getting the right kind of window AC is the first step in soundproofing a window air conditioner.
Make Sure the AC is Installed Properly
Purchasing a premium window AC is just as important as professional installation and the location of the AC. The window AC should be installed in an appropriate window and adequately spaced to avoid overheating.
Do not install your window AC in a corner. Also, check that there are no holes and spaces around the AC.
Consider Erecting An Insulated Wall
It's always best to insulate walls around HVAC systems and Generators to avoid causing noise pollution in your neighborhood.
You can use quiet fences, or mass loaded vinyl in combination with a sound absorber to reduce transmitted noise to the next apartment and through the walls of your home.
Conclusion: How to Soundproof a Window Air Conditioner
It’s time to eliminate all the unwanted sounds caused by your window air conditioner.
You have learned how to soundproof window air conditioner and quiet a noisy window AC without a costly replacement.
So, what's next? Start by determining which kind of sound you want to eliminate, whether that is outdoor sound, AC noise, or transmitted sound. Additionally, be sure to carefully follow the recommendations listed throughout this post.
You now have all the information to soundproof a window air conditioner, as well as information about the different types of unwanted sounds associated with window AC installation.