Senior Housing Towers Open in Manhattan and Brooklyn

Condo-style extras are also a selling point at the Watermark at Brooklyn Heights, a 275-unit property at 21 Clark Street that opened in early October.

Included in the facility’s 50,000 square feet of amenities are three restaurants, an art gallery and a pool, plus a skyline-gazing deck that sweeps across the roof of the building, the former Leverich Towers Hotel.

A blocklong Romanesque hulk that most recently served as a dormitory for the Jehovah’s Witnesses organization, the 1928 building, known for its four castle-like roof towers, was designed by Starrett and Van Vleck, the architectural firm behind Bloomingdale’s and other department stores.

The brick facade of the 16-story building has had landmark protection since the 1960s, so it hasn’t changed much. But few original details survived inside, according to Watermark Retirement Communities, a national firm that codeveloped the property with Kayne Anderson Real Estate and Tishman Speyer. In 2017, the developers paid $203 million for the building.

Watermark has restored a ballroom that the Jehovah’s Witnesses had partitioned into offices, to allow it to become the W Room, one of the complex’s restaurants. Lining its balcony is the art gallery, whose first show will be “Brooklyn Collected: Artists Next Door.”

Watermark has spent $2 million on personal protective equipment for staff members at some of its 62 complexes, which are found in 21 states, according to David Barnes, the company’s president. His mother lives in a Watermark property, though he hasn’t been able to visit her since March. “We are really pretty confident in our ability to create safe environments” Mr. Barnes said.

Of the 55 or so units leased so far in Brooklyn, no one has yet backed out, though not all tenants plan on moving in immediately.