The trend toward outdoor living, which uses comfy seating, bright rugs and weatherproof art to extend the al fresco season at home, is bringing new attention to a centuries-old architectural feature: the courtyard.

“It’s the original outdoor room,” said Philip Weddle, principal architect of Weddle Gilmore Black Rock Studio in Scottsdale, Ariz. “Courtyards are as much about enriching the indoor spaces as creating amazing outdoor spaces. That blurring of the boundary between indoors and out makes the experience of each space richer.”

Courtyards — a staple in Roman, Middle Eastern and ancient Chinese architecture — are becoming popular in homes throughout the United States, builders and architects say.

As they have for thousands of years, courtyards offer a safe and private area for families and guests to gather. In urban areas, especially, such secluded outdoor space is rare. Courtyards increase the amount of living space in a home. And when designed right, they can create a cooling retreat in warm climates.

Improvements in retractable glass walls and sliding doors have helped make them more feasible.

“That technology has really improved over the last decade,” Weddle said. “It really does allow you to open interior space to a courtyard more easily.”

People are accessing that outdoor space to cook, dine, entertain or just relax, Weddle said. He’s designed small courtyards that connect to a master bath and include an outdoor shower. “Courtyards come in all shapes and sizes,” he said.

Builder Nilay Bhatt, president of Dani Homes in Columbus, Ohio, also sees more Midwestern customers choosing courtyards: “It’s an element of outdoor living,” he said.

And in older suburban neighborhoods in Atlanta, Ed Castro Landscape has helped clients add courtyards to existing homes, said Hannah Seaton, a senior landscape design consultant with the firm. “They’re trying to turn an area of their property into a private place,” she said.

Luckily, the footprints of many older homes include nooks and hidden spots that lend themselves to courtyards, Seaton said.