How to Soundproof a Window

For any homeowner, noise pollution is a big problem. You might initially suspect that your walls are too thin, or your doors aren’t airtight, but check your windows as well. Windows are a common culprit for allowing sound into your home.

Let’s discuss 13 different methods to soundproof your windows.

While it’s important to sound proof your windows, there are other measures you can also take such as soundproof curtains. For a list of 2022’s best, check out our guide to the best soundproof curtains.

Can You Soundproof Windows?

Windows do not have a perfect seal. They are a great source of natural light, but they easily let in sound.

You can soundproof windows with a variety of methods. Soundproofing a window is a common DIY project, so there are many solutions. From sealing gaps with caulk to installing new triple-pane glass, you can enjoy a sound-free home.

How to Soundproof a Window

There are 13 different options for you to properly soundproof your windows. On this list, we’ve included every effective soundproofing method so that you can choose one that’s right for you.

Whatever your budget is for this project, you can easily find a soundproofing solution.

1. Seal Internal Window Gaps With Insulation Spray

Any gaps in the window will allow air and noise into your home. It’s important to have a great window seal to avoid these issues.

There may be some unfilled space left between the wall and the window. Even though you won’t be able to see these gaps from the outside, they can cause outside noise to ruin your quiet living space.

You’ll need to take the back end of a hammer and remove the window frame. Take expandable foam insulation and fill the noticeable gap between the wall and the window.

If there is a large gap, apply the foam from the bottom to the top. This way, it can stack on top of itself and not run down the frame. Fill the entire space, leaving no gaps.

The density of the foam will act as a sound barrier for the window. Replace the frame.

You can find foam insulation at a store for around $5, making this an inexpensive DIY project.

2. Seal External Gaps Around Window With a Caulking Gun

Windows are sealed with caulk, but these seals can develop gaps or holes. This will let in outside noise, so you might need to re-caulk your window seal. Making a brand-new seal can ensure there are no leaks or drafts around a window.

It’s best to inspect the current condition of the seal. If you notice any significant wear and tear or other signs of old age, continue to the next steps.

You can’t place new caulk onto the old seal. If you do this, the damaged caulk will fall off with the new seal. You’ll need to remove the damaged seal first. You can use a putty knife to scrape off.

To make a great seal, it’s important to remember a few things. Once you have caulk, don’t cut the tube tip too much. This will make the bead much larger, and windows need a very fine seal.

Once you’re ready to caulk, use both hands when using a caulking gun. You can slide it along the smooth window edge for the best application.

Acoustical caulk is a great choice for soundproof window seals. For less than $20, you can easily reduce the amount of sound that enters your home.

3. Add Weather Stripping

Weatherstripping is installed into windows to seal air leaks. When this is damaged, more sound can go through a window. Replacing the weatherstripping is an inexpensive project that effectively reduces outside noise.

Once you have taken care of the exterior caulking, you should replace old weatherstripping. Open your window and look at the current weatherstripping. If you notice any serious damage, it’s time to replace it.

Like acoustical caulk, weatherstripping is inexpensive. For around $5 for a full roll, this is one of the cheapest options on this list.

To install, simply peel off the old weatherstripping and apply a new strip. Weatherstripping comes with an adhesive backing for easy application.

4. DIY Window Plug

Building a window plug is a very effective option for soundproofing a window. Although you have to do all of the construction yourself, a DIY window plug can transform a room into a sound-free space.

Window plugs are constructed with a wood frame. Insulation and other soundproofing materials are packed inside it. Then you wrap the entire plug in a fabric of your choosing.

It’s important to measure correctly. Before you start building your window plug, carefully measure the window. The plug needs to fit snugly into the window space to be effective. If there are any gaps, sound waves will leak into the room.

The cost of a window plug varies based on the materials used. Medium-density fiberboard is ideal for this project, and this costs around $10 for a single 2 x 4. If you have a large window, the price could increase significantly.

A standard window plug will likely cost between $50-$100. This is because you’ll need many materials. To build a fully soundproofed window plug, you’ll need a tape measure, wood planks, foam board, foam tape, fiberglass insulation, mass-loaded vinyl, a saw, a drill, screws, a utility knife, and fabric.

5. Add Soundproof Window Inserts

Window inserts offer an easy installation process with great results. These are 1/4 inch acrylic panes that are surrounded by silicone compression tubing. When applied to a single pane window, they can reduce 70% of outside noise.

You can custom order a size that fits your window. Although they are more expensive than some other options, window inserts are a very convenient way to soundproof a window.

A standard grade window insert that blocks drafts and reduces outside noise will cost $30 per square foot. For an average window, this is around $360.

You also have the option of performance grade and commercial grade inserts. These cost at least $10 more per square foot.

Before you replace your thin, single-pane windows, consider getting window inserts. They are much cheaper than getting double-pane windows but can be just as effective.

6. Add a Carbon Absorption Panel

You can add carbon absorption panels to a room to dampen low-frequency sound waves. Their carbon technology absorbs unwanted low-frequency energy around the edges of a room. You can install these over windows to eliminate outside noise.

These panels come in different sizes and depths. The deeper the panel, the more sound waves it can absorb. You can order a panel that is 12 inches thick, reducing the interior noise level to 40 Hz.

Unfortunately, these panels are pricey. Some brands offer these panels for $100-$200. A more well-known brand, Acoustic Fields, sells carbon absorption panels for $850.

Although these can be effective, we’d recommend selecting a cheaper option before resorting to carbon panels.

7. Install a Sound Absorption Sheet

If you’re looking to transform a room into a place to practice a musical instrument or start a podcast, you’ll want to consider installing a sound absorption sheet. These can layer over windows and walls to improve internal sound quality.

Sound absorption sheets don’t block sound. They were made for reducing internal echoes and reverberation.

These are also a great eco-friendly option. Each sheet was made with recycled materials, so you won’t have to worry about your carbon footprint.

Like building a window plug, installing an absorption sheet will require a few more steps. Although they look similar to soundproof curtains because of their metal grommets, you won’t be able to simply hang them on a curtain rod.

When you order a soundproof absorption sheet, instructions will be provided. You’ll need to measure the space between the metal grommets. Measure the wall above the window, marking where you’ll place the grommets.

Drill a hole aligned with these marks. Insert the wall anchors and fasteners. Then you’ll be able to hang the sheets.

At around $100 per sheet, this option is more expensive than many alternatives.

8. Add Soundproof Barrier

You can control the amount of sound moving in and out of your window by installing a soundproof barrier. Whether you want a soundproof studio or need a quiet place to sleep, this can be a great option.

Soundproof barriers are sheets of padded vinyl. It is packed with insulation has a vinyl cover. You can choose a variety of colors, including black, white, tan, and gray.

Not only does this option reduce sound, but it also blocks light. It is also available as a clear panel if you want to keep natural lighting.

Soundproof barriers have metal grommets. This makes sure that you can raise and lower the panel easily.

The installation process is very simple. You’ll only need a tape measure, pencil, and scissors.

Each panel has a strip of velcro all around its edges. The manufacturer will send you a roll of velcro, as well. The velcro is 2 and 1/4 inches wide.

When installing your soundproof barrier, you’ll need to measure 2 and 1/4 inches around the entire window. Use your pencil to mark these areas. Measure the length and width using those marks as your guide.

Then order your panel as a custom size. After receiving your order, clean the wall around the window. Apply the velcro. You can then place the barrier over the window.

The smallest barrier panel you can order is 24 inches by 24 inches. This will cost around $300.

9. Add Noise Reducing Curtains / Blinds

Installing noise-reducing curtains is a great way to deaden internal echoes, although it doesn’t completely block external sound. They efficiently cut down on noise and keep out sunlight. With triple-weave polyester fabric, these curtains have a quality finish that will last for years to come.

Noise-reducing curtains have a sleek, modern style that won’t disrupt your home’s interior design. They are available in a variety of colors, so you’ll always find one that you love. This method of soundproofing will be the most aesthetic for your home.

These are very simple to install. If you already have a curtain rod, you can slide the metal grommets onto it. The installation process may take more effort if you need to install a rod.

You can find a great soundproof/blackout curtain for around $50. They will cost more if you order a customized curtain.

Like noise-reducing curtains, blackout blinds can also provide insulation against sound waves. Their honeycomb shape efficiently blocks UV rays, absorbs noise, and prevents heat loss.

These blinds have a cordless lifting system, which is much simpler to use than traditional blinds. They are also easy to clean and easy to install.

For less than $50, you can enjoy a sound-free space with noise-reducing blinds.

10. Add Window Film

Window film provides extra thickness to a window. Although this is usually to protect from a home invasion and UV rays, it can also reflect sound waves.

You can easily install window film without changing the original appearance of the window. This product is very DIY-friendly. When you receive your order, remove the protective film and stick the adhesive side to the glass. The manufacturer will provide specific instructions on how to avoid air bubbles.

This might not be the most effective option for soundproofing a window. Although a lab in Singapore is working on a sound-blocking window film, it has not been released yet. Regular window film may provide some protection against sound, but it was designed for blocking sunlight.

Window film costs around $15. This is one of the least expensive items on this list.

11. Double Glazed Coat

Chances are, you have single-pane windows. These are made with a single sheet of glass that doesn’t do a great job of blocking sound. Normal windows are not ideal for sound absorption, but you can install double-glazed windows to fix this problem.

Double-glazed windows are designed to decrease the number of sound waves that enter through a window. They have two layers of glass, separated by a layer of air. Sound waves are much less likely to travel through all of these materials.

A double glazed coat is great for sound insulation. The only downside is the cost. This process involves replacing the entire window, so you’ll have to pay for labor and materials.

Glazing costs around $200-$250 per square meter. Adding on the cost of professional help, you could end up spending a maximum of $1,000 per square meter.

This is a very effective method, but try out other methods first. There may be a cheaper option that is just as helpful.

12. Add Furniture

Everyone has furniture, but you may not know that it can be used to block sound. When placed strategically in a room, you won’t be able to hear those loud neighbors or busy street life.

When making windows soundproof, you can place furniture in front of them. A thick rug under a window can work wonders in absorbing sound waves. You can also move your couch or chair in front of the window. Sound is much less likely to travel through all those barriers.

This is one of the simplest, cheapest options on this list. If you already have furniture, it’ll be completely free. You might just have to rearrange some furniture.

13. Double or Triple Pane Windows

Sometimes covering a window with various soundproofing methods does not work. If you’ve tried every other option but are still bombarded with outside noise, considering replacing the window.

Double and triple-pane windows significantly reduce noise because of their extra layers of glass. Double-pane windows have two layers, while triple-pane windows have three. Each layer is separated by a layer of air, which effectively blocks sound waves.

Triple-pane windows will work better than double-pane windows. The more layers of glass there are, the more your window is insulated.

This can be an expensive process. Double-pane windows can have a price range of $450-$600 per window. For triple-pane windows, the cost increases even more. On average, the installation of triple-pane windows costs $550-$1,085 per window.

Cheap Way to Soundproof Windows

Not everyone can afford the price of fully replacing their windows. If you’re looking for the cheapest options, look for DIY methods with minimal materials.

From this list, the most inexpensive way to soundproof a window is to add weatherstripping. This material is very cheap, only $5 for a roll. It is also very simple to install. All you have to do is peel off the backing and apply a new strip to the window.

Caulk is also an inexpensive product. For around $20, you can apply a new bead of caulking around your window. When done properly, this method could save you the hundreds of dollars spent replacing a window.

Making a DIY window plug is another great, inexpensive option. If you already have a toolbox and regularly perform DIY projects, this method could be perfect for you. All the materials you’ll need to build a window plug will cost around $50.

How to Make Sliding Window Soundproof

Sliding windows commonly have many air leaks which allow sounds into your home. Luckily, many of the soundproofing options are similar to those listed above.

To make a sliding window soundproof, remove the casing and any old internal insulation. Use a can of spray insulation foam and fill the space.

Caulking can also be effective in soundproofing a sliding window. Make sure to remove the old caulking and replace it with a new bead.

Many of the other options on this list will work, too. Installing soundproof curtains or blinds can be one way to absorb internal echoes in a room.

Final Thoughts

Soundproofing a window doesn’t have to be a complicated, expensive process. You have the option of re-caulking the window seals, sealing internal window gaps with insulation spray, or adding weatherstripping. If you’d like a fun DIY project, a window plug might be a great solution.

There are many ways to cover windows to make them soundproof. Whether you install soundproof curtains or simply add furniture, you can easily transform your home into a quiet, private living space.