At 108 Leonard St., the building designed by McKim, Mead & White was constructed in 1894, originally for the New York Life Insurance Company. It became the Clock Tower Building, and the City of New York later used it as a courthouse and for galleries. After the building lay vacant for several years, the Elad Group and Peebles Corporation purchased it for approximately $153.4 million to convert to condominiums. When acquired in Dec. 2013, it was the largest New York City landmark building ever sold, according to Architectural Digest.

The 419,000 square-foot, 13-story building with an alternate address of 346 Broadway, is being converted to 151 luxury condominium apartments. Real Capital Analytics reports the estimated redevelopment cost is $400 million.

“There's a three-story clock tower on top of the building with the last of the manually operated clocks in North America,” said Zimmerman. A clock master, and later his assistant, came once a week to wind it manually—even when the building was vacant for 15 years. However, the owners planned to sell a $40 million penthouse with a four-side clock face, 10 feet in diameter on each side.

New York City's Landmarks Preservation Commission approved electronically automating the clock. However, non-profit preservation groups filed a lawsuit claiming it should be preserved as one of the few remaining mechanical public clocks and the clock tower should remain open to the public. An appellate court affirmed a lower court's ruling against the developer, who has filed another appeal.

“We're not sure what's going to be done with the clock tower but the building is being restored beautifully in anticipation of becoming condominiums,” said Zimmerman.

Alchemy Properties, for $68 million acquired the tower portion of the Woolworth Building. Ken Horn, the real estate development firm's founder and president, referred to the structure as the “grande dame” of landmark buildings.

Alchemy is refashioning the structure into luxury condominiums. Originally designed by Cass Gilbert, the historic neo-Gothic building. located at 233 Broadway, was constructed in 1912 as the F.W. Woolworth Company headquarters. The tower portion has the address of 2 Park Place.

The Landmarks Preservation Commission authorized the developer to make changes, including increasing window size, expanding floor area, adding a pavilion, and topping the building with a pinnacle. To preserve signature aspects of the Woolworth Building, the developer paid attention to specific design details.

A craftsman from Canada removed the porcelain and plaster tiles from Frank Woolworth's 40th floor office. He bathed them in sea kelp and baby shampoo, and “treated them like they were his children,” said Horn. He restored 60 tiles, which will be placed in the residential lobby. Designers also duplicated the WW logo from the elevators, placing them in the kitchens.

Alchemy spent $22 million restoring the terra cotta exterior of the building, replacing 3,500 pieces. “No matter what we do going forward, this will probably be the most complex historic landmark that we've ever done,” said Horn.

John Cetra, the founding principal of the CetraRuddy architecture firm, is converting the former Mount Sinai St. Luke's Hospital at 30 Morningside Drive, between 113th and 114th streets, to luxury rentals. Purchased by Delshah Capital in 2016 for $111.5 million, the development cost is projected to be $250 million for the four pavilion Beaux-Arts structures.

The original architect, Ernest Flagg, constructed the building from 1895 to 1929. At the time air conditioning and modern mechanical systems did not exist. The hospital needed to provide ventilation, light and air naturally. “So, he created a building, a series of beautiful pavilions based upon the French revival chateaux style,” explained Cetra.

Flagg designed chimneys that were not for ventilating fire and smoke but to bring fresh air into the buildings. He constructed multiple zigs and zags to get natural light and ventilation throughout the building. There were balconies on every floor for patients to get fresh air. “You want natural light, ventilation, outdoor space, beautiful architecture. All of these things fit beautifully for taking a hospital and turning it into a rental building,” said Cetra.