Air Conditioner Window Seals (6 Best Options & How To Guide)

Home climate control has never been easier. With so many different types of air conditioners for your home on the market, you shouldn’t have an uncomfortable day, ever. However, portable AC units and some window units leave large gaps in our windows.

Needing to vent outside, unless you have a single hung window, you may be out of luck. Until now. This article will compare and review the various types of air conditioner window seals.

These AC window seals allow you to properly vent your air conditioner without having to leave a window open or be exposed to the elements. Read on to learn more.

6 Best Air Conditioner Window Seals Reviewed

In this section, we compare the 6 best air conditioner window seals, reviewed and rated just for you. Each type has distinct advantages (and disadvantages). Scroll through the list and find the best fit for your AC and window.

1. HOOMEE Universal Window Seal

HOOMEE 300CM (118") Universal Window Seal for...

Our top pick for best air conditioner window seal is the HOOMEE Universal window seal. This cloth window seal is weather-resistant and waterproof to give you even better control.

You can install it with the included adhesive strip and hook loop fasteners. You won’t need to buy or use any other system to keep your portable AC hoses inline and venting outside. With a double zipper, this model also accommodates ACs with dual vent hoses.

While it is a universal fit, you still need to get the right size for your window. This particular model comes in 4 different sizes. The dimensions are measured as the circumference (in centimeters) around your window.

The standard size is 300cm, but they also offer a 400 and 560cm window unit and a 36 x 83 inch model for use around doors.

The cloth material and waterproof zipper prevent warm air, insects, and weather from entering your home while in use. Best of all, you don’t need to remove the system to use the window.

If you decide you don’t want to use the AC, you can remove the hoses, open the zippers and use your window as usual.

It also collapses when you close the window, so there is no need to remove it. This fit will work on casement, single and double-hung windows, as well as top or bottom mount skylights, awning windows, and doors.

What We Like
  • Fits almost any window size and type
  • Simple installation
  • Dual zipper for multiple hoses
  • Waterproof and weather-resistant
What We Don’t Like
  • Instructions aren’t very clear
  • Only one color available

2. Airly Window Seal For AC Unit

Window Seal for AC Unit – Window Seal For...
  • KEEP THE HOT AIR OUT – The whole point of...
  • NO MORE INSECTS – tired of flies and...

If you have a portable AC and casement windows or awning style windows, this is the window seal for you. It attaches easily, collapses for window closure, and uses a zipper for vent hose placement.

Installation of this seal can be completed by a single person in less than 5 minutes. Everything you need comes in the box, including the cloth seal and double-sided tape.

You will need to clean your window frame and mounting location for proper adhesion, and cut the tape to size, though.

Unlike our top pick, this system is best used for casement windows only, though awning-style windows can also use it. Unfortunately, if you have a window with a perimeter larger than 158 inches, you can’t use this one.

It only has one size option. Smaller windows will also have a billowing seal. While it still works, it can make it difficult to close the window completely.

Once installed, though, you will be able to use the zipper section to place your vent hose. The cloth material is water-resistant and insect-proof. You will also notice that warm air stays out and direct sunlight remains outside, helping your AC stay more efficient and cool faster.

What We Like
  • Simple installation
  • Works best with casement windows
  • Insect and water-resistant
  • Durable construction
What We Don’t Like
  • Only one size available
  • Tape can come loose in high heat

3. BROSYDA Hung Window Seal

Brosyda Portable AC Window Kit, Air...
  • 【Adjustable Universal Size】Our air...
  • 【Prevent Cooling Air Escaping】The window...
  • 【Seal Window Totally】With high-quality...
  • 【Upgraded Detail Surprise】We will set a...

For homeowners with sliding windows and hung windows, the air conditioner window seal from Brosyda is the one you want to look closer at. This model is made from premium polyester and Velco.

It offers a simple installation process and comes in two sizes with variable sizes in each.

The smaller size is the most common. Used primarily for hung windows, you can attach to frames from 22 to 36 inches wide. If you have a sliding window and it is taller, you can opt for the larger size. It accommodates openings from 40 to 59 inches.

To install, you only need to clean the adhesion area on the frame and sill of the window and attach the Velcro strip. The cloth seal will then attach to the Velco strip and seal off your window. You can then use the center zipper to attach the vent hose.

If you need to close the window, you can simply close it. The thin cloth material is weather and fade-resistant but lays flat and won’t interfere with the window locks.

If you want to use the window, you only need to unfasten the Velcro on the frame side, and you can then use your window for fresh air at any time.

What We Like
  • Perfect for sliding and hung windows
  • Thin cloth folds easily when closing window
  • Two sizes for multiple window widths or heights
  • Prevents weather and insects from entering
What We Don’t Like
  • Only fits a single vent hose
  • Zip tie needed to prevent zipper opening

4. habibee Universal Window Seal

habibee 157"(400CM) Universal Window Seal for...
  • UNIVERSAL - Suitable for portable mobile air...
  • HIGH QUALITY MATERIALS - Made of 190T...
  • EASY TO INSTALL - You don't have to buy...

The universal window seal from habibee is one of the most cost efficient models on the market. There are, of course, cheaper versions available, but those less expensive options tear easily or have a difficult time staying attached.

With the habibee seal, you get a higher quality material that lasts a lot longer.

Unlike other low-cost options, this version doesn’t billow out and fits your window nicely. Like our top pick, there are four sizes to choose from to get a better fit. They include perimeter measurements of 300, 400, 500, and 560 cm. There is not a door frame option, though.

Once you have the right size measured and ordered, installation is a breeze. Everything except the cleaning chemicals is included. You even get a microfiber cleaning cloth to wipe off the areas on the window where the hook loop tape will attach.

Ideal for casement and awning style windows, you shouldn’t use this type of seal for hung windows or bottom-pivot swinging and skylight window types.

It does have a zipper for a single vent hose, but double hoses can be used if they have enough clearance to mount in either corner of the seal.

What We Like
  • Lightweight cloth design
  • Everything needed for install included
  • Perfect solution for casement windows
  • Fits portable AC vent hoses
  • Multiple sizes
What We Don’t Like
  • Won’t work with hung windows at all
  • May need two people to install

5. AGPTEK Window Seal

AGPTEK Window Seal for Air Conditioner,...
  • 【Wide compatibility】Portable air...
  • 【Great Quality】Our window seal for air...
  • 【Novel Design】 Our window slide kit plate...
  • 【Extra Protection 】Our window seal for AC...

AGPTEK has a different window sealing solution., Instead of a cloth or polyester material, they use sturdy PVC that can expand to fit horizontal or vertical installs. Not made for awning, skylight, or casement windows, this is the ideal solution for sliding and hung windows.

The touch PVC plates slide together to adjust to fit your window from 26 to 47 inches. It also has a hose attachment that fits all standard 5-inch vent hoses from the most popular portable AC models on the market.

You also don’t have to worry about the plates sliding apart or together. There are mounting screws that keep them in place. Once you have the plates in the window, simply slide out to fit snugly and tighten the screws.

After that, you only need to attach your hose with the twist-lock attachment, and you are good to go. Also, if you find any gaps or have a smaller hose, the kit includes 3M sealing tape to prevent drafts and air leaking.

What We Like
  • Ideal for sliding and hung windows
  • Built-in hose holder
  • Seal gaps with included tape
  • Quick install by one person
What We Don’t Like
  • Doesn’t fit casement windows

6. Duck Brand Premium Window Air Conditioner Insulating Foam Seal

Duck Brand Premium Window Air Conditioner...
  • Duck Brand premium air conditioner insulating...
  • Place seal on top of the unit and lower...
  • High density foam creates a weather-tight...
  • Each foam seal is 0.5-Inch thick by...

We haven’t forgotten about those with window mounted ACs, either. Portable ACs don’t get all the fun! For window mounted ACs, though, you don’t need a lot of options, and they generally fit snugly in the window sill, with small gaps here and there.

For those gaps, you can use a lot of materials to fill them, but none are better than Duck brand insulation foam. This roll of weatherproof, water-resistant, and insect-resistant foam will slide, squish and flex into the smallest gaps.

You also have tape options that let you place a barrier all the way around your air conditioner to seal gaps on both sides (inside and outside) that you may not see.

Once you have it installed and the window closed down, drafts, weather, rain, bugs, and hot air are kept outside while the AC is left to cool the inside more efficiently and faster.

With a simple foam seal installed, you can make your system more efficient, use less energy and save money on your monthly energy bill as a result. Each kit contains enough foam sealant for a single-window AC, so you won’t need to worry about leftovers, storage, or buying more.

What We Like
  • Easy install steps
  • Weatherproof
  • Can help lower monthly energy costs
What We Don’t Like
  • List
  • List

Air Conditioner Window Seals Compared

HOOMEE 300CM (118") Universal Window Seal for...
Window Seal for AC Unit – Window Seal For...
Brosyda Portable AC Window Kit, Air...
habibee 157"(400CM) Universal Window Seal for...
AGPTEK Window Seal for Air Conditioner,...
Duck Brand Premium Window Air Conditioner...
HOOMEE 300CM (118") Universal Window Seal for...
Window Seal for AC Unit – Window Seal For...
Brosyda Portable AC Window Kit, Air...
habibee 157"(400CM) Universal Window Seal for...
AGPTEK Window Seal for Air Conditioner,...
Duck Brand Premium Window Air Conditioner...
HOOMEE 300CM (118") Universal Window Seal for...
HOOMEE 300CM (118") Universal Window Seal for...
Window Seal for AC Unit – Window Seal For...
Window Seal for AC Unit – Window Seal For...
Brosyda Portable AC Window Kit, Air...
Brosyda Portable AC Window Kit, Air...
habibee 157"(400CM) Universal Window Seal for...
habibee 157"(400CM) Universal Window Seal for...
AGPTEK Window Seal for Air Conditioner,...
AGPTEK Window Seal for Air Conditioner,...
Duck Brand Premium Window Air Conditioner...
Duck Brand Premium Window Air Conditioner...

What Do Window Seals Do for AC Units?

Window seals come in a variety of shapes, sizes, and materials. You will find felt and rubber seals, similar to weather stripping, and PVC seals for single hung windows to help seal the actual unit.

There are, though, PVC, plastic, and vinyl coverings that protect the window itself. They also allow for ventilation of a portable AC hose and help keep heat, sun, insects, and other debris out of the home while the window is in use.

With these seals, you can properly vent your air conditioner without worrying about recycling hot air, overworking the machine, or causing improper moisture accumulation. By keeping your window and AC exhaust sealed properly, you can increase efficiency and lower energy costs.

Advantages Of Using AC Window Seals

AC window seals have a few advantages over not using anything at all or using other methods of sealing. Not only are they easy to use and install, but the added benefits are hard to ignore.

Keep The Hot Air Out

One of the biggest benefits of window seals is that they prevent warm air outside from getting in. With the purpose of your air conditioner to cool the air in your home, you don’t need warm drafts making it more difficult.

Warm drafts are responsible for lowering efficiency and keeping the system running longer.

Barrier Around The Window Frame

With the portable air conditioner hose mounts, you don’t protect your window, and there isn’t a barrier around the window to keep it secure or in place. If the window pane moves at all, the entire hose can fall back into the home.

Be it a single hose or a dual hose portable AC, with a window seal, your exhaust hose will stay in place, and your entire window can be protected.

Keep The Insects Out

With portable and window AC units, the biggest drawback is that your window needs to be open. This allows drafts and warm air to enter, but it is also an entrance for insects and bugs.

A properly installed window seal will close off these openings and keep nature outside the window where it belongs.

Added Security

While window seals aren’t a security device, they can help prevent a possible break-in. Thieves and robbers look for easy access and open windows.

With a window seal installed, your window appears sealed, clocked, and not an easy point of egress. From a distance, most thieves will continue on, looking for an easier access point on another home. Covering your window AC is something we believe is worth considering if you can manage it.

Considerations When Choosing Window Air Conditioner Seal

Before you head out and buy the next window seal you find, there are certain factors to consider. Below, we outline the major concerns you should take time to think about before you buy.

The Installation Process

Installation of the seal can be complicated depending on the size and type of window, as well as the size and type of window seal. There are several attachment types, including screws, adhesives, double-sided tape, hook tape fasteners, and more.

Most will also require two people to get installed correctly, but once installed, you shouldn’t have much problem with the use or adjustments by yourself. Make sure you read the instructions and follow all steps provided to ensure a smooth install.

The Seal Material

Along with various attachment types, there are also various materials the seals can be made from. The most popular is a canvas or cloth. They are machine washable and easy to care for. You also have PVC or plastic options that are more durable, but stiffer and less forgiving.

There are also felt and rubber options as well as combination models that use more than one material. Finding the best fit for your needs will depend on your care and maintenance needs as well as window type.

Window Seal Material

Vent Fitting

If you have a portable AC, the venting will be the biggest issue. Some models have a single hose, and others have dual hoses. You will need to ensure your window seal can accommodate the venting needs of your system.

Some types are designed for multiple vent hoses, either with zippers or different vent ports. Others have a single access that will need to be manipulated to fit the different models.

Buying a universal model is a good idea if you are unsure, but a better fit is one designed for your type of AC, specifically.

Most Common Window Types That AC Seal Can Be Installed On

Air conditioners can be installed in a variety of window types. Portable ACs are the most versatile as they only need a small access port for exhaust. However, different windows provide different challenges for proper sealing. Let’s take a closer look.

Single & Double-Hung Windows

Single and double-hung windows (one moving sash or two moving sashes) are among the most popular window types in residential homes.

These vertical lifting (or dropping) windows need special seals that can cover the width of the window as well we the height it is opened to accommodate the air conditioner mounted in it.

If you have a window air conditioner, you may get by with only needing the felt or rubber weather strip style sealer. For portable AC vent hoses, you will need the zip or adhesive bag style. These will fit the width of the window and allow a port for the vent hose.

Casement Windows

Casement windows are the biggest type in need of a proper window sealer. Because they typically don’t have screens, using the adhesive and zipper style seals will keep warm air, sunlight, and insects from entering the window.

Most will also accept two vent hoses using double zippers or access holes.

Slider Windows

Slider windows work best with adjustable seals. The zipper bag style is most commonly used here. Because you adjust how far the window opens, you need a seal that expands to match and can collapse without causing difficulty closing or locking the window when not in use.

Awning & Skylight Windows

Specialty windows like awning and skylight styles need specific accommodations. If the pivot is in the middle, you may be out of luck, unless you use two different seals. However, for top or bottom pivot mount windows, the zipper bag style used on casement windows will also work here.

How To Seal Window Air Conditioner: Lower Temperature & Energy Bills

Among the largest of the benefits of window sealing are the increased energy efficiency, lower in-home temperatures, and lower monthly energy bills. To get these additional benefits, though, you need the right seal, and it must be installed properly.

While the various window seals and window types will play the biggest role in how to proceed, you will also need to check the instructions included. However, below we offer a few tips and guides to sealing a window gap and sealing a window for a portable air conditioner.

How To Seal Air Conditioner Window Gap

Window gaps occur when there is a misalignment of a window unit or if the sill is not flat or level. Gaps can occur around the unit itself, the vent hoses, or even just from an offset window pane. For smaller gaps, you can use a weatherstrip style seal, foam, or rubber.

You may wish to use expansion foam for medium to large-sized gaps if it is a permanent install. Otherwise, you will need to reposition the window unit, position the corner with a brace or fill the gap before using the foam sealer.

How To Seal A Window For Portable Air Conditioner

When sealing for a portable window, there are a few ways to go. First, almost all portable units come with a PVC or plastic window slide that fits in the window with a slot designed for the exhaust hose.

If you plan to use the slide, you can still use a window seal around the entire apparatus. The zipper bag-style sealers are ideal for this situation. The zippers are made to go around the vent hoses and can attach to the window frame.

Most of these types will have adhesive hook-loop tape that attaches to the wall around the window or the frame itself. Once attached, the hose fits in its space, and your window is complete.

With the window open, the seal will expand without extra work, and when closed, it will collapse without needing removal.

Seal Window for Portable AC

People Also Ask (FAQ)

How do I bug proof my air conditioner?

With open windows, bugs will always be a problem, but you can lessen the threat of their encroachment. Closing blinds and curtains at night will help minimize any light they may be drawn to.

You can also spray around the window sill and AC unit with bug spray to help keep them away. If possible, the use of a window screen or a cloth window seal will keep them from getting inside.

How do you seal the outside of a window with an air conditioner?

Sealing the outside of the window isn’t generally required. However, if there is a gap or spacing that allows a draft even with the inside of the unit is sealed or closed, you may need to take a few precautions.

First, you can use weather stripping to seal smaller gaps. You may also find use with spray foam or rubber sealer.

Is it absolutely necessary to seal an AC?

There isn’t a requirement to seal your air conditioner. However, not sealing can cause drafts, lower efficiency, and allow insects into the home. With the benefits, a proper seal will save you time, effort, and money, so it is highly recommended.

Where can I buy window seals online?

You can find the best selection and lowest prices online shopping at sites like Amazon. You can also find AC parts and window sealers at other air conditioner outlets like Sylvane.


Air conditioner window sealers are great for helping your window or portable AC unit maintain efficiency and keep your energy costs lower. You can purchase a window sealer and install them in a short amount of time.

With cloth and plastic zipper models, they are easy to clean, collapse so you can still use the window when needed and lock it when closed. These seals work for all types of window air conditioner units but specialize in portable air conditioners and their vent hoses.

One of the best options is the HOOMEE Universal Window Seal, our top pick. It fits almost all types of windows and has dual zippers to accommodate portable air conditioners with dual vent hoses.