Contents (Click To Jump)
Why Do Windowless Rooms Get Hot?
Rooms without windows get hot for the same reasons any other rooms in your home get warm. Usually, they warm up as the outdoor weather gets hotter. They can also get warm from lighting, electronics, appliances, or from many people occupying the space.
For example, if your washer and dryer are in a windowless room, they will generate a lot of heat and warm the room.
What Should You Do To Cool Down A Hot Room?
If you have a room in your home without windows that is constantly too hot, you might be wondering how to cool it off. If only the room had a window! Then you could use a window AC unit.
If you’re scratching your head trying to figure out how to cool down your windowless room, there are a few paths you can take. Some are easier and less expensive than others, but all are viable solutions.
Install a Window
If your hot, windowless room has an exterior wall, you can consider installing a window and window air conditioner. Having a window installed is generally not a cost-effective option to get cooling into a room. However, it provides other benefits, such as natural lighting and perhaps more resale value.
If your room does not have an exterior wall, then you cannot have a window installed. You have to look at alternative cooling options to remove the hot air.
Get a Through-The-Wall Air Conditioner
Compared to installing a window, installing a through-the-wall air conditioner is less expensive. For this option, the room will need to have an exterior wall. Essentially, a square hole is cut into the side of your house, and an air conditioner is permanently mounted in the hole and sealed.

A through-the-wall AC unit is not ideal for most homeowners, but it effectively cools windowless rooms.
Use a Portable AC Unit
A portable AC unit is similar to a window AC unit that sits on the floor. It has wheels and an exhaust pipe that mounts to a window. However, if your room does not have windows, the exhaust pipe can be mounted through a vent that exhausts outdoors. The exhaust looks similar to a dryer vent.
This option would require a specialized vent and incur installation costs. It is one of the more economical solutions for homeowners.
Use a Swamp Cooler
A swamp cooler, or portable evaporative cooler, cools rooms through the evaporation of water and ice. They are energy efficient and work particularly well in dry, arid climates. They work by blowing warm air across cool pads or coils, which cools the air before recirculating it into the room.
A simple homemade version of this is placing ice or cold water in front of a fan.
Install a Ceiling Fan
Ceiling fans will circulate air around the room and could reduce the temperature if it sucks in cooler air from other parts of the home. Remember, ceiling fans can’t cool the air; they only move it. So if you’re running a fan with the door shut, your room won’t get any cooler, but it could make the room feel cooler.
Shade Your Home
If your windowless room is on the south side of your home, it will experience direct exposure to sunlight most hours of the day, unless it has shade from the sun. If your windowless room is in such a location, consider planting trees, bushes, or other shrubberies to shade your home from the sun and keep your windowless room cool.
Alternatively, you can install an awning, pergola, or other man-made structure to provide shade.
Improve the Airflow
If your room with no windows already has ductwork leading to it, you might have an easy fix.
Perhaps all you need to do to improve its cooling is provide sufficient airflow into the room through the existing ductwork. The duct might be clogged with dust and debris, or a damper may be partially closed.
Additionally, the ductwork itself might be disconnected or have lots of leaks.
In any case, our team of experienced HVAC professionals can diagnose the issue and provide a solution.
Connect the Room to the Central AC
If the windowless room is not connected to your central air conditioning, you can install a ductwork extension. Depending on the distance from your central air conditioning systems, this could be a costly endeavor.
If you’re considering this option, make sure your air conditioning unit is a large enough capacity (size) to handle it. Our HVAC team can help you determine this.
Install A Ductless Mini-Split Heat Pump
Ductless mini-split heat pumps provide both heating and cooling to rooms, depending on their setting. Best of all, they don’t need windows to operate.
Mini-split units have an indoor unit that gets mounted on the wall of the room and an outdoor unit that sits outside. They are connected by refrigerant lines that transfer heat from one location to the other to heat or cool the room.
Ductless mini-split heat pumps are simple, economical, efficient, and versatile. They are the best solution to cooling a room with no windows and should be one of the top options for homeowners if they can afford them.
Hacks For Cooling Down A Room With No Windows And AC
If you’d rather not pay the extra expense of installing additional HVAC equipment just to cool your windowless room, there are plenty of DIY hacks you can utilize. Here are some out-of-the-box methods to cool a room without windows.
DIY Swamp Cooler
You can make your own swamp cooler with a bucket of ice and a fan or two. This might sound odd at first, but the air blowing across the ice will cool the air, which will, in turn, cool the room. Make sure you place the ice in a bowl or bucket that is large enough to hold the ice when it melts into water.
If you sit in front of the fan, you will feel cooler than if you were not directly in front of it. So position the fan and yourself wisely. This easy DIY trick is a quick way to cool a windowless room, but it is not a permanent solution. The ice will quickly melt, and you will have to reload it. However, it is still less expensive than installing a through-the-way air conditioner.
Double Fans
A neat trick you can implement to cool your windowless room is to use the two-fan method. Place one fan blowing air into the room and one fan blowing air out of the room.
The double fan trick works best if the fans are different heights and even better if the room has two doors (like a short box fan and a tall stand fan). In that case, place the intake fan blowing in on door number one and the other exhaust fan blowing out on door number two.
Turn off Lights and Appliances
Turning off lightbulbs and any heat-generating devices will help keep your windowless room cooler. Electronics that generate heat include:
- Incandescent Lights
- Computers
- Gaming consoles
- TVs
- Washer and Dryers
- Speakers
- And more
Keep the Doors Closed
If you keep the doors to the windowless room closed, isolating the room could prevent heat from entering the room from other areas of the home.
Keep Yourself Cool
Sometimes there is only so much you can do to lower the air temperature in the windowless room. If you’ve tried many things and still feel too hot, change your focus to lowering your body temperature.
Drink cold beverages, wear light fabrics, eat cold foods, and take a cold shower if you’re up for it.
What Air Conditioners Are Best For Cooling Down A Windowless Room?
The best air conditioners for a windowless room are all AC systems that do not require a window. Therefore, window air conditioners are out, and everything else is good.
Central AC System
Connecting your central air conditioner to your windowless room is one of the most effective ways to cool it. The central AC will pump cold air directly into the room and keep its temperature the same as the rest of the home.
If you can stomach the upfront cost of installing ductwork, this is the least intrusive and cleanest method (once construction is complete).
Through-The-Wall Air Conditioners
A through-the-wall air conditioner is essentially a window AC unit that’s installed in a hole in your wall instead of a window. Sounds beautiful, right? Unfortunately, most homeowners don’t think so. However, it is a simple free-standing solution that is an affordable and viable option for cooling a windowless room.
Ductless Mini-Split Heat Pumps
A ductless mini-split heat pump, or ductless air conditioner, is a somewhat unobtrusive device. They have two major components– an indoor unit that mounts on the wall of the windowless room and an outdoor unit that sits outdoors next to your home.
They are connected together with refrigerant lines that transport heat to or away from the room. The refrigerant lines need less than a 3-inch diameter hole to pass through, making the installation process simple and inexpensive.
Mini-split systems can heat and cool the windowless room. A clear bonus if you live in a region that gets both cold winters and hot summer weather.
Portable AC Units
A portable AC unit is like a window unit on wheels. Instead of hanging out your window like a sore thumb, a portable unit just has a small exhaust tube that snaps into the window.
However, if you don’t have a window, you can have an exhaust hole cut through the wall to the outdoors. Once the vent hole is installed, the portable air conditioner will exhaust the same way as your clothes dryer, minus all the lint.
How Can An HVAC Contractor Help?
Our team of experienced HVAC professionals can analyze your windowless room and suggest the best options for cooling the space. They will provide a quote for the most feasible solutions, along with the pros and cons of each.
They won’t decide for you, but will deliver you an informed opinion on what will do the best cooling job for a reasonable cost. If you’re looking for an honest quote and not just a recommendation the most expensive option give our team a call today.