Film is defined as a thin coating or covering. I will stick to that definition for the purposes of this article, and not clutter it up with blankets, curtains, or brick walls.
Sound is caused by vibrations travelling through the air or another medium (like window glass), that can be detected by the human ear. Almost anything you put over your window will help with soundproofing–some products quite a bit, some very little–because even thin films slow vibrations in glass. Here are some options for your consideration.
Note: If you are looking for more substantial window soundproofing ideas please see our articles:
7 Best Soundproof Window Films
Most people opt for window film soundproofing because they want, or need, access to the light and/or fresh air. In addition to making the room quieter. If light and/or fresh air is not that important to you, the more options there are for window film soundproofing. You may have great soundproofing curtains, blinds, or shutters for night time but prefer to let the sun in during the day, but keep the noise out at the same time. Here are a few things that could be part of your decision-making process.
- Light. Do you want, or need, natural light in the room?
- Access & Egress. Having the ability to open the window for air may, or may not be, important to you, but building codes have pretty stringent egress requirements for bedroom windows–covering opening sizes, hardware, etc. that could affect your choice of soundproof window film. The specifications almost always consider fairly small children, so even having a piece of plastic restricting access could get an inspector or insurance company frowning at you.
- Privacy. Some window film is obscure to provide privacy. Some is clear.
- Looks & Appeal. Window films come in a variety of designs and colors, from clear to black, patterned to obscure.
- Insulating Value. Adding a layer of film to windows can help with keeping the heat in and cold out.
Once you have decided on what is important, then you can choose from one of the items listed below.
1) Noico 80 mil Butyl Automotive Sound Deadener
If you do not care about natural light, but are looking for great soundproofing, then Noico 80 mil Butyl Automotive Sound Deadener may be your answer. Weighing 0.7 lbs./square foot, it is a tremendous soundproof film. Designed, and used to dampen and deaden cabin noise in vehicles and improve audio sound, it is used for many other soundproofing projects. It is 80 mils thick. (1 mil = 1/1000 of an inch making the Noico 2 mm or .08″ thick.)
It is simple and easy to apply directly to the glass. Clean the glass with vinegar or glass cleaner like Sprayway Glass Cleaner. Noico is self-adhering butyl with a paper peel off back. Fit the pieces to the glass, then peel off one edge of the backing paper, stick the edge to the glass, and press the Noico onto the glass. Once stuck to the glass, roll the foil side flat with the Noico roller (sold separately).
The interior finish choices are shiny aluminum foil or black aluminum foil. Rolled flat on the glass it provides soundproofing film and still allows access to window handles, latches, locks, and cranks.
For more product information and/or product uses please see our articles: Kilmat vs Noico vs Dynamat vs Hushmat and How to Fix Car Speaker Rattle.
- Excellent sound deadening product
- Thin 0.08″ thick
- Heavy 0.07 lbs./square foot
- 2 colors – shiny aluminum and black
- Easy to apply
The Not so Good
- Eliminates view outside and incoming light completely
2) Magnetic Window Insulation Kit
The Yuzzy Magnetic Window Insulation Kit is generally purchased more for its insulation value than for soundproofing. But because of its tight fit and full coverage of the complete window frame, it will double as a noise deadener. Unlike the ‘glue-on with a hair dryer’ options, this magnetic film allows quick and easy access to the window sash, handles and locks without the need to destroy it. Just remove the film from the wall mounted magnet, open or close the window, and replace the window film.
The package comes with a roll of magnetic tape, a roll of grooved magnetic tape, plastic strip, EVA plastic film, accessory bag, and instruction manual. Measure your window and buy the next size bigger. (Always easier to cut off a little extra than trying to stretch it.) The manufacturer says it takes about 15 minutes to install one. Being a firm believer in Murphy’s Law, I would plan on about a half hour. This is a fairly durable product and can be re-used for a few years. Just remove the film every spring, wash with mild dish detergent, rinse and snap it back in place to dry.
The film works as a soundproofing agent by creating a partial dead air space between glass and film making sound waves lose a little vibration energy before passing through.
- Inexpensive insulation kit that fits most windows
- Easy to install
- Tear resistant and waterproof
- Chemical resistant
- Film can be replaced with fiberglass bug screen for the summer. (Do not use metal mesh.)
The Not so Good
- Not as good at soundproofing as some of the other products.
3) rabbitgoo Window Privacy Film
The rabbitgoo Window Privacy Film is available in multiple sizes and styles to suit your needs. It blocks 84% of UVA rays and 99% of UVB rays to protect floors and furniture from fading. It also provides some soundproofing by being attached to the window glass and reducing sound wave energy vibrations somewhat. The privacy protection level is about 60% and it is not recommended for bathrooms.
Rabbitgoo films are cling film. In other words they require no glue to attach them to the glass. Cut them to size, remove the clear backing material, and fit the piece onto the glass. Make sure the glass is clean–either vinegar and water or glass cleaner. (Note: Removing the backing material appears to be a little finicky, but once started, it will come off easily.) Because of the static cling design, it can be removed and re-applied multiple times.
- Stylish soundproofing and sun blocking window film
- Multiple patterns & multiple sizes
- Blocks 84% UVA rays and 99% UVB rays
- Static cling installation
- Removable and reusable multiple times
- Privacy level of about 60%
The Not so Good
- Soundproofing ability not as good as some other films
4) Duck Brand #286218 Five Window Shrink Film
Duck Brand #286218 Five Window Shrink Film is available in different sized packages from one door size to 10 window size. It is attached to the outer perimeter of the window casing providing a partial dead air space between glass and film for added soundproofing. If applied properly, it will help keep out heat, cool breezes, and some sound.
To install, apply the tape to the perimeter of window casing. Cut the film about 2″ wider and 2″ higher than the needed. Stick the top to the tape, then sides and bottom. Press firmly. Keep as smooth as possible. Use a hair dryer to shrink the film until snug.
Although I saw one review suggesting this film is reusable, I have never seen any that I would be bothered to try salvage. It is inexpensive and works very well when installed new. Trying to save it to re-use–specially when your need to buy more shrink film tape–strikes me as a ‘Saving Money Dumb’ exercise.
The manufacturer also offers a maximum strength insulation kit with puncture resistant film making it somewhat child and pet resistant. And a better soundproofing product.
- Inexpensive soundproofing and insulation kit
- Multiple sized packages
- Quick, easy installation
- Use hair dryer to take out wrinkles
- Maximum strength puncture resistant film available
The Not so Good
- Not reusable
- Not the best soundproofing material on this list
5) Second Skin Luxury Liner – Mass Loaded Vinyl
Second Skin Luxury Liner – Mass Loaded Vinyl is a black 2 lb. per square foot product that can be taped onto the glass of a window. With an STC rating of 32, it will definitely stop most of the noise trying to come through your window. It will also stop all of the light. But because it is attached to the glass you have access to handles and locks, allowing you to open the window without removing the MLV. Other options are to tape it to the casing, which will cover the entire window opening. If you are planning to cover the complete window frame anyway, give some thought to buying a grommet maker, installing grommets on one side and hanging it from hooks. This method allows easy removal when, and if, required.
You can also find clear MLV at Acoustical Solutions. Use clear double-sided tape to attach it to the glass. (Note: I have never seen this product, so I do not know how ‘clear’ it is.)
- Sound Transmission Class (STC) rating of 32
- Great sound blocker
- Available in black or clear
- Quick easy installation
- Made in the USA
The Not so Good
- Does not allow light into the room
- A bit pricey
6) BDF S8MC Security Window Film
BDF S8MC Security Window Film helps prevent glass breakage–from storms, crooks, peaceful demonstrators, and other idiots. It is also 8 mils thick making it a great product to reduce glass vibrations caused by noise. Making your room/house a bit quieter. Another benefit is its 99% reduction of UV rays helping to keep the house cooler and preventing fading of carpets and furniture.
Link to Safety Glazing Standards for a little more information ANSI Z97.1 Class B CPSC Category 1 testing requirement that this security film meets. The BDF film is a glue-on product with serious adhesive to meet the required glazing standards. Once installed it is not easily removable.
The manufacturer claims a DIY friendly installation process. Each package comes with a utility knife, squeegee, and instructions for cutting and installing. It is perfectly clear and if installed properly, virtually invisible. Available in multiple sizes.
- Heavy 8 mil adhesive window film
- Primarily sold as a security film
- 99% reduction of UV rays
- Available in multiple sizes
- Comes with utility knife and squeegee (I would be looking for a slightly bigger squeegee for large windows.)
- USA company
The Not so Good
- Some comments about trouble installing smoothly. Also some comments about ease of installation.
7) The Future of Soundproof Window Films
A group of scientists in Singapore has invented a window film that acts like noise cancelling headphones. The 3 layer laminate contains a polymer interior speaker sandwiched between 2 strong layers of clear plastic. The speaker part of it will not only play music but works to cancel incoming noise. Potentially it can work with the windows either open or closed. See a report about this very interesting soundproofing breakthrough in The Straits Times.
Unfortunately for anyone wanting this product, it appears that the scientists may need some time to perfect things. And maybe more time to get it to commercial production. No timeline was given, but years was mentioned.
How We Chose Soundproof Window Film
One of the things that kept me going while writing this article is the Three Decibel Rule. Who is going to believe that putting the equivalent of stretch and seal on a window will lead to any sound reduction? Really! About as smart as Egg Carton Soundproofing . . . It Doesn’t Work, which we covered some time ago. But . . .
Acoustical window film helps by reducing the ability of the glass to vibrate, thereby reducing sound transmission. By cutting down on vibration, the window film/glass combination ‘absorbs’ noise because fewer frequencies pass through undiminished.
Window film works best on thick heavy glass, or dual glazed windows, or laminated glass because they are already quite good at soundproofing and vibration reduction. But you might see the best improvement using film on 3 mil single glass because anything that stiffens the panes up will cut down vibration, with cuts down sound transference.
Note: 3 mil is pretty standard glass thickness.
It never hurts to have a decibel meter handy. Check the noise before your modifications and after. Make sure you are standing in the same spot both times to get truly comparable readings.
The 3 Decibel Rule & Noise Blocking Window Film
The 3 Decibel Rule states: “Every 3dB change represents a doubling or halving of sound energy”. Meaning that if my window film is capable of reducing airborne noise by even one decibel, let alone 3 decibels, I have accomplished quite a bit without spending too much time and money. Of course, the heavier material like Noico 80 and Mass Loaded Vinyl will perform much better, but as noted, the draw back of eliminating natural light may put them out of the running. They also cost significantly more than other window films–cling-on, glued, or magnet style. And the futuristic ‘music-playing window film’ may never come to market.
For an easy-to-understand full explanation of the 3 Decibel Rule please follow this link to Pulsar Instruments.
Soundproofing the Rest of the Window
I promised not to clutter up this article with window plugs, blankets, curtains, etc. and I won’t. But I do need to mention gap filling. Gaps between the window frame and wall, or unsealed casing, or windows not locking and sealing properly. Any type of, and size of, hole, gap, crack will allow sound into the room. Wherever air can move, so can sound. Make sure that all of the gaps are sealed up before blaming the glass.
- Window Locks/Latches. A window sash not closing the last 1/4″ will let in a lot of noise. Make sure handles, latches, keepers, and all related hardware are working properly.
- Window Weatherstrip. Even the best operating hardware will not be efficient if the window is missing weatherstrip. There are so many types and styles of weatherstrip used in so many types and styles of windows that getting a proper match could require a little research. Manufacturer, model, and year of production. Two of the best sources of window parts are allglassparts.com> and windowpartscenter.com>. One of the more versatile products is Torrami Felt Pile Weatherstrip.
- Perimeter Sealing. Remove the interior casing, spray about 1″ of foam sealant against the back of the exterior trim, let it dry, fill the balance of the cavity with rockwool or fiberglass batt insulation (packed loosely), replace the casing, and seal it to the wall and window jamb with paintable caulking.
Use your decibel meter to check noise before and after sealing the gaps, then again after applying your window film for an honest assessment of what you have accomplished.
FAQs About Soundproof Window Film
Here are a few questions that come up when people consider window films for soundproofing.
Does window film really reduce noise?
Yes. Window films attached to the glass reduce the ability of the panes to vibrate. This ‘absorbs’ noise by slowing down or eliminating the glass vibrations needed to permit sound frequencies to continue traveling with the same energy.
Is 3M window film good for reducing noise?
Yes. Because it is glued onto the window casing instead of the glass, the 3M film creates a bit of a dead air space between glass and film which will deaden the sound energy before it gets to the inside of the room. Also if your window does not fit well, the 3M film will cut down on wind noise.
Does window film block bass sounds?
Not really well. Bass sounds are the low frequencies–generally between 20 Hertz and 200 Hertz–which will even travel through concrete. Bass noise also creates vibrations that window film will not slow down much, if any. For more information on bass soundproofing please see our article How to Keep Bass From Going Through Walls.
Can windows be made soundproof?
Yes. But it is quite difficult. You are starting with the weakest part of the wall in many ways–including soundproofing. The most effective method is to remove it, frame, insulate, and finish the hole making it a wall. Otherwise, you are having to use a combination of window film, window plugs, soundproof blankets or curtains, or shutters. If the noise is loud enough, it is almost impossible to soundproof anything.