We expect buildings to physically age better and last longer than people. And well they should. But the Glass House, which Philip Johnson designed for himself in 1949 in New Canaan, Connecticut, never looked dated or old. As it readies for its public opening this month, it still appears as up-to-the-moment as the day Johnson posed at the house (top), on July 1, 1949, on the verge of his 43rd birthday. Even in 1974, when the Architectural League of New York helped Johnson (far left in photo, above) celebrate the 25th anniversary of the house with a picnic, the pristine steel-and-glass pavilion hardly looked like a period piece. Only the guests’ attire and hairstyles give the year away.