Can You Install A Portable Air Conditioner In A Casement Window?

If you are thinking about getting a portable air conditioner to cool down your home, but you aren’t sure whether it will work with your windows or not, don’t worry.

If you have a casement window, it can be discouraging because of how tricky they are. However, it is possible to vent your portable air conditioner out of a casement window. 

Can you Install a Portable Air Conditioner in a Casement Window?

It might be easy to dismiss the idea of a portable air conditioner if you have a casement window. Most portable air conditioners only come with an installation kit for a traditional window, so that means you can’t install it in a casement window, right?

 Luckily, that is not the case. You can install a portable air conditioner in a casement window if you know what you need to do. So, what do you need to do? Let’s take a look!

How to Install a Portable Air Conditioner in a Casement Window

To use a portable air conditioner in your casement window, you will need to make a slight adjustment to your window. It is highly recommended to use Plexiglas as an addition to your window with a hole cut in it for the vent to go through. Plexiglas is recommended because it can keep the hot air outside your home and keep the cool air in.

The first thing you will need to do is measure your window. This will tell you what the size of the Plexiglas will need to be. You can get the Plexiglas cut to the perfect size at any hardware store. They will also cut the hole for you, so you should take the vent with you so the hole can be cut to the proper size.

After you get your Plexiglas, you can start installing it onto your window. You will start by cranking open the window and attaching a latch to both the window and the frame. Next, you will need to attach the Plexiglas to the window frame. You can do this with twist clamps or retainer clips. 

After you have the Plexiglas in place, you will need to caulk around the edges where the casing meets the window frame. This will create a seal to keep water out when it rains and keep the hot air out and the cold air in. You could also install a weatherproof strip instead of caulking if you prefer.

After you have the Plexiglas installed and sealed, you need to attach the hose to the vent and enjoy your air conditioning!

Which Portable Air Conditioners Can You Use in Casement Windows?

There are so many portable air conditioners out there with different kinds of vents for cycling the hot air out of your home. When you are looking to install a portable air conditioner in a casement window, it will be best to find a unit with a round or square vent. This will make it easier to cut the Plexiglas to fit the vent.

In most cases, portable air conditioners will come with these kinds of vents, so there is no need to worry. Just make sure that you choose the right size of portable air conditioning unit for the room you are trying to cool down, and you will be good to go.

Importance of Portable Air Conditioner Placement

The placement of your portable air conditioner is important for the safety of the unit and your home. The unit should always be placed on a floor that is hard and level.

It is also important to keep the unit between 8 and 12 inches away from furniture and walls. The manual that comes with the unit will give you the specifications that they recommend.

You should never place your portable air conditioner on a desk, shelf, or chair. These units are designed specifically to operate on the floor, and they will not work right if they are not appropriately placed. Improper placement like this could damage the air conditioner. 

You also need to make sure that the power cord can reach the outlet without needing to stretch. If the cord is stretching to reach the outlet, you might want to consider a different place to install the unit.

You also need to be sure that the hose isn’t stretching to reach the window. You want to keep the hose as short and straight as you possibly can.

Why Not Use a Window Air Conditioner?

You might be wondering why you would use a portable air conditioner instead of a window air conditioner. Window air conditioners hang out of the window and aren’t very attractive to look at.

In some cases, homeowners’ associations won’t even allow for window units to be installed. Portable air conditioners do not stick out of the window at all.

Portable air conditioners are much easier to install in casement windows than window air conditioners are. To install a window air conditioner, you need to take apart the window before installing the unit. When you install a portable air conditioner, you don’t have to take apart the window at all. 

Security When Using Portable Air Conditioners

If you are installing the portable unit on the first floor, your home’s security might be a concern for you. If you install the portable air conditioner in your casement window with Plexiglas, you don’t have much to worry about. While your window will technically be open, the Plexiglas is attached to the window frame.

That means if someone were to try to get into your home, they wouldn’t be able to without breaking the Plexiglas. Another bonus of the Plexiglas is that it is incredibly difficult to break. While it is possible to break, it would be difficult to do without you or someone in your home hearing the commotion. 

Why Size of Portable Air Conditioners is Important

The size of the portable air conditioner you buy is important because you want to be sure that it has enough power to cool down the size of the room you are putting it in. Portable air conditioners are sized by BTUs, or British Thermal Units, per hour. 

Units with a higher BTU rating will be able to give you more cooling power. You want to make sure you buy the right size to save you energy and money.

If you have a room with standard 8-foot ceilings, it is simple to determine what size you need. A portable air conditioner with 8,000 BTUs will be able to cool 200 square feet of space, 10,000 BTUs will cool 300 square feet, 12,000 BTUs will cool 400 square feet, 13,000 BTUs will cool 450 square feet, and 14,000 BTUs will cool 500 square feet

It is imperative to have an accurate measurement of the room you are putting the portable air conditioner in because while it is possible to have an undersized unit, it is possible to have one that is too big.

If you are using a BTU unit too high for space, the unit will cool quickly but will cycle through to maintain the temperature. This will result in an overworked unit and a higher electric bill. You might also have a humidity problem with a unit that is too big.

If the unit you are using has a BTU that is too low for space, it will run nonstop and overwork itself to reach the set temperature. You will have a hot room and a higher electric bill, along with wasted money on the unit that can’t do its job. 


If you wonder whether or not you can install a portable air conditioner in a casement window, the answer is yes. The process might even be easier than you expected, too. All you need is some Plexiglas cut to fit your window, some caulking, and the air conditioning unit. You can have the unit installed in no time at all.

When it comes to the security of using a portable air conditioning unit with your casement window, there isn’t much to worry about there. When you install the Plexiglas, you are attaching it to the frame of the window. Even though your window will appear open, there will be no way in through the Plexiglas unless it gets broken.

Plexiglas is very strong and sturdy, making it hard to break. You will likely hear someone trying to break it before they can succeed and make it into your home. Using a portable air conditioner is entirely safe and secure.

As long as you choose the correct size portable air conditioner for the room, you are trying to cool. You should not have any issues with using your unit in a casement window.