A house currently under construction near Highlandville spans almost a full acre from wall to wall, on a 500-acre site. The ambitious project, nearly three years in and barely at the first floor, totals 72,000 square feet.

Putting that figure in perspective might require a few comparisons. According to the Census Bureau, the average new home size over the last five years was between 2,100 and 2,500 square feet. Springfield's Pythian Castle is between 34,000 and 39,000 square feet, said owner Tamara Finocchiaro. Microsoft founder Bill Gates' house is 66,000 square feet.