Miniature staircases are having a moment. “Made to Scale: Staircase Masterpieces,” which spotlights staircases collected by Old Masters collector Eugene Thaw and his wife, Clare, went on display last week at Cooper-Hewitt, National Design Museum. The vintage models have become popular with serious collectors, and Pottery Barn offered much cheaper reproductions in its summer catalog.

First created by cabinetmakers in France and England in the 18th and 19th centuries, mini staircases were whittled to prove one’s mastery in the art of cabinetmaking. The Thaw collection includes one particularly intricate set of steps in the 17th-century Italian style with an open dome; it had been previously owned by fashion designer Bill Blass. A double helix staircase is also on view, and another sports Sèvres porcelain busts of Voltaire and Rousseau.

Just a few decades ago, however, staircases were considered purely decorative, not fodder for serious collectors. But the market changed dramatically with Sotheby’s 2003 auction of the collection of Carter Burden, a city councilman and philanthropist. One double spiral staircase zoomed past its modest $1,500–$2,000 estimate to fetch $32,400. Three years later, period staircases sell for up to $35,000 retail.

Why the sudden boom? “They’re interior architecture in miniature and they ring chic,” a Manhattan antiques dealer, George Glazer, who offers both antique renditions as well as reproductions, said. Other staircase dealers include Mallett Antiques and Philip Colleck in New York, and Axel Vervoordt in Belgium.

Another factor in their popularity is that the staircases are rarities these days. “Normally, we see one or two period ones a year, if that,” Sotheby’s English furniture expert, Simon Redburn, said. “For someone to build an entire collection is really exceptional.”