(Rendering by Hartman-Cox Architects)

The historic neoclassical Patterson House at 15 Dupont Circle in Washington has been watching over the changes in the neighborhood since its completion in 1903.

The ornate, intricately carved limestone mansion, home to President Calvin Coolidge and, most recently, the headquarters of The Washington Club, one of the city’s oldest women’s social clubs, is the midst of its own transformation.

Demolition work has been completed, setting the stage for conversion of the mansion into 93 fully furnished studio apartments.

[From ladies’ club to luxury apartments: The Washington Club bids Dupont Circle farewell]

Manhattan Construction is managing the project for SB-Urban LLC and Rooney Properties, the building owners and joint developers. Hartman-Cox Architects has designed the interiors for the building, which has been listed on the National Register of Historic Places since 1972. The mansion was designed by architect Stanford White of McKim, Mead & White and is the only remaining example of his work in Washington.

The 25,000-square-foot five-story mansion and a new 42,000-square-foot, eight-story addition will include a workout facility, a library, a dining room with a large shared kitchen, a bar and party area and an outdoor terrace for residents.

Michele Lerner is a freelance writer. To pass on a tip or news item, contact us at realestate@washpost.com and put “Town Square” in the subject line.