When an apartment or penthouse isn't big enough for wealthy New Yorkers, they get creative.

In recent years, several have combined multiple townhouses or building floors to create supersized homes — or Frankenmansions, as New York magazine's S. Jhoanna Robledo calls them.

To construct these Frankenmansions, some prospective buyers purchase multiple buildings at once, while others approach their neighbors to offer multimillion-dollar buyouts. (In either scenario, they need the city's approval before combining properties.)

Check out these 12 Manhattan Frankenmansions owned by big names — including Madonna and Sarah Jessica Parker — outlined below in red.