Thornton Tomasetti Sustainability Project, One John Street In Brooklyn, Receives Leed Gold

Tomasetti, the international engineering firm, announces that One John Street, a 12-story, 42-unit luxury residential building in Brooklyn, New York, has achieved LEED v2009 BD+C Gold certification from the U.S. Green Building Council.

Working with Alloy, the project owner/developer and architect, Thornton Tomasetti provided sustainability consulting services for the 125,000-square-foot building in Brooklyn Bridge Park. The building was completed in August 2016 at a cost of $42 million.

Key Points

• Thornton Tomasetti was retained in the early design stages to develop a sustainability strategy that targeted a minimum 50 percent reduction in greenhouse gas emissions. In addition to LEED consulting services, it provided energy modeling and building science analysis, which led to improved thermal performance of the building envelope and increased overall energy efficiency. The firm also helped right-size HVAC system design and select controls for improved comfort and performance.
• A number of sustainable measures employed in the building have resulted in both energy and cost savings. These include the installation of high-efficiency HVAC systems, the use of locally sourced and recycled materials, such as Forest Stewardship Council (FSC) certified wood floors and cabinets, and LED high-efficiency lighting.
• Low-flow fixtures reduced water use by 30 percent, equating to an energy savings of 24 percent above code. A cogeneration plant that produces electricity and transfers waste-heat to the building’s domestic hot water supply helps to reduce fuel consumption as well as other energy costs. A variable refrigerant flow system is also used to transfer heat throughout the building via a load sharing method.
• One of the project’s challenges was minimizing traffic and subway noise to ensure resident comfort. Thornton Tomasetti implemented a selection of progressive glazing with a triple-pane window system that improved the acoustics as well as the thermal envelope of the building.
• The windows of One John Street become progressively smaller as the building ascends. Thornton Tomasetti performed a thermal analysis to reduce thermal bridging and increase insulation around the windows, which resulted in greater energy efficiency thanks to integrated design.