More than 35 million Americans have no air conditioning at all, and millions more have it but can’t reliably run it. With a dangerous heat dome building across the eastern U.S. this week, it’s important to stay cool as much as you can. Here are some affordable ways to keep cool this summer.

Minimize heat entering your home

In order to keep cool during high heat, you want to minimize the heat entering your home. You can do this by keeping your blinds closed during the day to block the sunlight from shining in and heating up your home. Blackout curtains work even better.

Then, in the early morning and late evenings when it's cooler outside, opening your windows will allow some of the cooler air to enter. If you can, open windows that are across from each other to create a cross breeze that flows through your home. 

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You can also leave out a bowl of ice because as the ice melts, it draws heat out of the environment, cooling the area. If you have fans, keep them running because any additional circulation will help.

If you need immediate relief from heat, use wet washcloths to cool yourself or take a lukewarm shower. 

DIY cooling systems 

If you live in low-humidity regions, make yourself a DIY swamp cooler using a bucket, electric fan, zip ties, PVC pipes and water or ice. The swamp cooler reduces temperatures by blowing air over water or ice to cool your space by up to 15 degrees. However, this doesn’t work if you live in humid conditions, as the added humidity from the cooler will increase discomfort. 

Instead, if you live in high-humidity areas, turning on a dehumidifier is your best bet. If you don’t have one, you can use a bucket of rock salt or baking soda to absorb the moisture in the air. 

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Seek relief in public cooling spaces

During the day, when the heat is at its peak, consider visiting public spaces that have air conditioning to seek relief. 

Public libraries are a great, reliable choice that are open to everyone and most offer wi-fi, restrooms and water fountains. 

During heat emergencies, cities will also open designated cooling centers to anyone. In New York City, LinkNYC kiosks will display real-time walking directions to the nearest cooling center within a 10-minute walk. In Washington, ReadyDC offers a variety of resources, such as finding the nearest cooling center. 

You can also search “[your city] cooling center” to find more information about cooling centers near you. 

There are also plenty of museums in major cities that are free or have free days, which could be a great alternative to seeking heat relief while also being entertaining and educational. 

In New York City, the National Museum of the American Indian and the American Folk Art Museum are always free. The Metropolitan Museum of Art (The Met) is pay-what-you-wish for New York residents. 

In Washington, all Smithsonian museums are free every day, which includes the Air and Space Museum, the Natural History Museum, etc.

In Philadelphia, the Philadelphia Museum of Art is pay-what-you-wish on the first Sunday of each month and every Friday evening. In Atlanta, the High Museum is free on the second Sunday of every month. 

Heat is the leading cause of weather-related deaths, especially in a brutal, persistent heat wave. If it gets too hot in your home, it is important to know when to seek help.