But like much of American society, the middle-class home began to grow over time. The average size of an American house in 1950 was 983 square feet. Slowly, though, both more square footage and more amenities became part of the American dream, so that by 2004 the average home topped 2,300 square feet.

What does all that space bring? Small, out-of-the-way bedrooms like those in the Levittown houses’ “expandable attics” can be used when children are at home or guests arrive, and the open plan of their main living spaces has become the kitchen/family room that is the center of the American home today. But many of the “must-have” elements in 2010, like formal living and dining rooms, are redundant. In an era of economic austerity and a seemingly permanent energy crisis, can “less is more” become popular again?

Sadly, many of the small, architect-designed houses of the postwar period have been demolished to make way for McMansions. But those that remain, and those we know about from blueprints and photographs, have much to teach us — about the efficient use of space for storage, integrated indoor and outdoor space and the way careful design can facilitate natural ventilation. When you think about how many rooms you actually use, it seems obvious that various ideas from that optimistic era could make the next decade a happier, saner one than the overstuffed times we’ve just lived through.