How to cool down a room without windows – 5 simple solutions for sealed-off spaces

Whether it's an internal room or the windows don't open, these five methods can cool down a room without external air

A cozy snug with l shaped sofa
(Image credit: Andrew Frasz)

Most of the time, when we are a little too hot, we simply throw open a window and enjoy the nice breeze – but what if your room doesn't have windows? Or the windows don't open? 

There are plenty of ways to cool down a room, even without windows, it just requires a little ingenuity, no matter if you have an internal bathroom space or an enclosed cinema room.

Here, air quality experts have explained five ways you can keep a windowless room cool with and without air conditioning for chilled summer days at home. 

How to cool down a room without windows

If you have AC, then turning this on is a logical first step, making sure the filters are clean. Ensure any internal air ducts in your home are clean and free from obstructions too, to help with the flow of cool air, suggests Lane Dixon, VP of operations and air quality expert at Aire Serv.

Lane Dixon
Lane Dixon

Lane is the VP of operations at Aire Serv, a Tennessee heating and air conditioning specialist. They specialize in installation, maintenance, and repair, and have become one of the nation's most trusted brands for air conditioning.

Fan in a darkly lit room, surrounded by plants

(Image credit: GettyImages)

1. Invest in a portable AC unit

If you do not have a central AC unit, then a portable AC unit, available at Amazon, is your next best bet. Of all the air conditioning types, these are best for smaller rooms. They come into their own in situations where you do not need to cool your whole house at one time, offering an eco-friendly way to keep a room cool while helping you to save money at home

‘These devices contain a compressor, which is responsible for cooling the air, and a hose which leads to a ventilation port and, although portable air conditioners can be a bit noisy, they are an effective method of reducing the temperature and humidity in a room,’ explains Erica Frecundo, tiny home building specialist at Hauslein. ‘They have the added benefit of being able to be moved from room to room, making them a highly versatile option.’

2. Run your ceiling fan counterclockwise

If you have a ceiling fan, then changing the fan direction to cool a room is an effective way of drawing cool air into the space, and pulling warm air away from you, recommends Lane Dixon. 

‘The counterclockwise circulation of fan blades in the summer pushes cool air down to the floor, producing a wind chill effect on the skin and making a room feel up to eight degrees colder to those underneath. Ceiling fans also help your air conditioner, redistributing already chilled air, and reducing the need for constant central or window air conditioning,’ he explains.

3. Have a professional install a mini-split system

If you want to keep a home cool in a heat wave, and prepare for future hot temperatures, then you can install a mini-split cooling system to offer a permanent cooling option, suggests Mark McShane, HVAC expert and trainer at Skills Training Group

‘A ductless mini-split system can be a great solution for cooling down a room without windows. These systems are designed to provide both heating and cooling and can be mounted on a wall or ceiling to provide chilly air without the need for vents. 

‘I would advise, however, to have a professional install this system in order to get the maximum benefit,' he adds. 'This can also mitigate some health and safety aspects of installing such a feature yourself.'

4. Use an evaporative cooler

Evaporative coolers, also known as swamp coolers, are a great option for dry climates or small spaces. They are also great if you are looking to cut energy bills, as they do not require any electricity. 

These coolers, HVAC expert Mark McShane explains, use a fan to draw in hot air and pass it over water-saturated pads to cool it before pushing it back out to the rest of the room, decreasing the overall internal temperature. Just remember to regularly swap out the pads to keep it efficient. 

5. Reduce sources of heat

In windowless rooms, it is important to limit the amount of heat being generated to make your cooling option more effective.

To do this, you should turn off unnecessary electronics, choose energy-efficient appliances which are less likely to expel energy through heat, and either turn off lights or switch to energy-saving light bulbs, at Amazon, suggests Ben Green, HVAC expert and founder of Green Leaf Air

In the case of small, windowless bathrooms, avoiding taking hot steamy showers is also recommended, as is leaving your extractor fan running to pull humid air out. 


How do you get rid of hot air from a room?

You can force hot air out of a room by positioning fans angled towards an open door, this will blow hot air out while also creating a cool slip stream. You can make this process easier by increasing ventilation in a room by opening windows where you can, ensuring vent ducts are clear from obstruction, and reducing sources of heat by turning off electronics, or using energy saving alternatives. 

Is it better to leave a door open or closed when hot?

In the heat it is best to leave your doors open to allow the flow of air and your home's humidity, making you feel cooler and preventing your room from feeling stuffy. If you cannot have your door open for whatever reason, try to open windows, or otherwise use a dehumidifier or air purifier to keep air in the room moving. 

It can also be a good idea to open windows in adjacent rooms and position fans close by to help blow cool outside air inwards to the rest of the house. When combined with other cooling techniques, your internal rooms will be more comfortable in no time. 

Chiana Dickson
Content Editor

Chiana has been at Homes & Gardens for two years, having started her journey in interior journalism as part of the graduate program. She spends most of her time producing content for the Solved section of the website, helping readers get the most out of their homes through clever decluttering, cleaning, and tidying tips – many of which she tests and reviews herself in her home in Lancaster to ensure they will consistently deliver for her readers and dabbles in the latest design trends. She also has a first-class degree in Literature from Lancaster University.