New York City developer Harry Macklowe and global architecture firm Gensler have proposed a 96-storey office tower in Midtown Manhattan, which could become the city's tallest skyscraper by roof height.
Details of the proposal, named Tower Fifth, were acquired by the New York Times last week when Macklowe submitted the preliminary application to the Department of City Planning.
The developer ? who was behind Rafael Viñoly's 432 Park Avenue ? has enlisted Gensler to lead the design, while local practice Adamson Associates Architects will serve as the architect of record.

Tower Fifth is intended to be built on a plot along Fifth Avenue, between 51st and 52nd streets.
Designed to reach 1,556 feet (519 metres) tall, it would become the city's tallest skyscraper by roof height. But One World Trade Center, which reaches 1,776 feet (541 metres) to the top of its mast, would still retain the official title. To build his tower, Macklowe will have to acquire air rights from the surrounding buildings ? the majority likely to come from nearby St Patrick's Cathedral.
Renderings of the skyscraper proposal show a glassy, rectangular structure punctured with square windows ? almost like a sister to 432 Park Avenue. The exterior will be clad in an "expensive and energy-efficient facade rarely seen in the United States", according to reports.

At the top, the skyscraper would segment into three volumes. The lower block would cantilever out to host "the city's tallest observ...