The first building at 505 State Street is 482 feet (147 m) high and contains 441 residential units and a retail base.

Construction was delayed in the early 2020s, due to the COVID-19 pandemic in New York City, and the office space was removed from the plans.

[2][3] The completion of the project was contingent on the rezoning of the site owned by Alloy and the New York City Department of Education so that two towers can be built and floor-area ratio can be tripled.

[4] Local community members feared that 80 Flatbush as originally planned would cast large shadows around Boerum Hill and Prospect Heights, since one of the towers was originally supposed to be as tall as the Chrysler Building, which is 1,046 feet (319 m) tall.

[5][6] In August 2018, New York City Council member Stephen Levin announced that he would seek a height reduction.

[15] The number of apartments at 100 Flatbush would increase from 257 to 441,[12][16] and the residential address of that tower was changed to 505 State Street.

[20] 505 State Street topped out during January 2023,[21][22] and the developers launched an affordable housing lottery for first tower's affordable-housing apartments that October.

[27] Alloy Development refinanced 505 State Street that December with a $290 million mortgage from New York Life Real Estate Investors.

The architectural website Dezeen compared 505 State Street to Manhattan's Flatiron Building, which also occupies a triangular site.

[18] The market rate and affordable apartments contain the same interior decorations because Alloy Development founder Jared Della Valle wanted the design to be "democratizing" as opposed to "polarizing".

[30] Robertson's firm, RR Interiors, decorated several model apartments using secondhand furniture from sources such as Craigslist.

[32] Alloy Development is also partnering with the nonprofit BRIC to turn a building on the site that will not be razed into new spaces for the organization.