With heat waves hitting the U.S., more people are using air conditioning, which is bad for the environment and expensive.

But there are other ways to keep cool. Los Angeles and New York, for example, have started repainting rooftops white to reflect heat.

And, for centuries, people in hot climates have built sustainable buildings that can handle the heat.

John Onyango, a professor at the University of Notre Dame School of Architecture, suggests that the U.S. has become complacent due to cheap energy, neglecting innovation. He proposes that we can learn from Middle Eastern countries like Iran, Dubai, and Turkey to reduce heat.

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For example, in Abu Dhabi, a building uses wind towers to cool down, lowering temperatures by up to 50 degrees. This works by funneling hot air from outside to the lower floors where it cools naturally. This method doesn’t need electricity and can be used in high-rise buildings.

Prof. Amin Al-Habaibeh of Nottingham Trent University suggests high domed roofs can enhance a building’s cooling ability by dispersing heat from the sun. Using natural materials like stone and mud can also help make buildings more heat resistant. These methods might be more expensive initially, but in the long run, they save money on air conditioning.

As temperatures rise, U.S. cities will need to make changes, like repainting rooftops white to reduce heat or planting more trees. It makes sense to borrow techniques from places used in hot climates. However, the initial costs of traditional architecture and materials may deter developers, despite long-term savings from reduced air conditioning costs.

Read more at Time.com.