rooftop

ulkokatto, vesikatto, katto atop Atop a roof; on a roof

In recent years, we've seen Bangkok become the unofficial rooftop bar capital of the world.

—Thailands Islands and Beaches'', Lonely Planet

Why do you think the rooftop of their apartment building is called "tar beach"? (Answers may vary.)

—Multicultural Books for Primary Grades, Liz Rothlein

The house itself was a mound of red baked bricks and a tin rooftop.

—The Chocolate Shop Perverts, Ernest Alanki