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100 Flatbush

Set to become the first all-electric residential tower in Brooklyn, with electrical power replacing components normally run by natural gas.

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Project Details

Project Partners
Alloy Development
Brooklyn, New York
Completion Date
375,000 ft²
840 ft
Number of Stories
100 Flatbush in Brooklyn. Thornton Tomasetti
100 Flatbush in Brooklyn. Thornton Tomasetti
100 Flatbush in Brooklyn. Courtesy Alloy Development
100 Flatbush in Brooklyn. Courtesy Alloy Development
100 Flatbush in Brooklyn. Courtesy Alloy Development

Brooklyn’s first all-electric residential tower

The 1-million-square-foot mixed-use Alloy Block development in Brooklyn consists of two residential towers sitting on a podium with commercial, office, cultural and retail spaces along with two public schools that will also serve community organizations. The 44-story 100 Flatbush tower is part of the first phase of the five-building mixed-use development. The tower will have 396 market-rate and 45 affordable units and 30,000 square feet of retail space.

The complex also houses the 350-seat Khalil Gibran International Academy—the city’s first public school building designed to Passive House standards. It comprises an elementary and a high school, and features classrooms, reading rooms, labs, libraries, playground and terraces, dining areas, student support spaces and administrative spaces.

We are providing sustainability services to Alloy Development for the complex's first tower (100 Flatbush), and the educational facility, which are on track to be completed in 2024.


  • The residential tower maximizes energy savings through the use of sustainable interior finishes, targeting a window to wall ratio of at least 45 percent, a water source heat pump with a perimeter heating system, keeping perimeter heating to a minimum and reducing glare by manipulating the façade design, and integrating nature and natural systems into its landscape and overall design.
  • The school façade comprises a continuous insulation layer and an airtight envelope that will efficiently maintain comfortable interior conditions. This will reduce heating and cooling demands for the mechanical systems as well as primary energy demands for the entire school.
  • The school will further maximize energy savings by incorporating well-placed, well-sized and high-performance windows to fully light classroom spaces, using 60 percent widow to wall ratio as a rule of thumb and requiring ventilation to meet ASHRAE 62.1-2013 at minimum.
  • The school demonstrates a 35-40 percent energy savings from an equivalent 2016 NYC-EEC code compliant building and is on track to achieve a 29 percent energy savings.

Our Team