The Judges in the 2015 Engineering Excellence Awards Competition have selected 837 Washington for a 2015 ACEC New York Gold Award in the category of Structural Systems.

Situated across the street from the High Line in Manhattan’s Meatpacking District, 837 Washington Street is a six-story office & retail development designed by Morris Adjmi Architects for Thor Equities & Taconic Investment Partners and built by Sciame. Our firm served as structural design engineer. The building is a new torquing tower that rises out of an existing 2-story Art Moderne style brick warehouse built in 1938, which was once part of the Gansevoort Market.

With 12’+ ceiling heights throughout, the building consists of 28,000 SF of retail space, 27,000 SF of office space, and 7,000+ SF of roof-deck & terraces. Structural work on this project was completed in September 2013, with an estimated total project cost of $96 million.

To comply with complex landmark restrictions, the design team preserved the original masonry façade, created new masonry openings at street level, and restored cantilevered canopies that are signature to the neighborhood. This lower retail structure frames into a new steel exoskeleton of sloping columns and twisted floorplates, designed to echo the angles of neighboring streets.

The unique torso of 837 Washington provided opportunities for creative approaches to its structural design. Steel beams rotate around brick cores that tie back into the warehouse structure below. The intricate design was achieved by creating innovative plate girders. These were fabricated off-site by Weir Welding and shipped to the site for assembly. The skewed profile of these customized girders allowed architectural/visual perpendicularity of the design to be maintained.

The nature of the sloped column design results in a tendency for the building to twist under its own weight and occupancy. While some movement may be acceptable, the tolerance of this rotation had to be engineered so as not to damage the curtainwall. The beams and columns were proportioned to attain the necessary stiffness, situated crossbracing around the building core (out of the way of interior use), and designed bolted column connections with connector plates at interior of flanges as well. Furthermore, the building was engineered for live loads higher than required in order to allow for greater flexibility of use in the future at the retail levels.

One consequence of an exoskeletal system is that the steel frame is exposed to the elements and is prone to thermal conductivity. This problem was resolved by allowing only the beam web to pass through the building envelope and employing non-metallic carbon fiber thermal break shims for these connections, thus thermally isolating the exoskeleton from the building interior

The building is designed to achieve LEED Gold Certification. The structure has been designed to support planting beds along the edges of floor slabs that reduce storm water runoff and roofs were designed to sustain rainwater retention loads, among other strategies. Logistically, despite being situated on a tight urban site, construction was achieved efficiently, with minimal disruption to the immediate streets and surrounding neighborhood.

The building stands as a case study of how a design can pass through Landmarks respecting neighborhood context and maintaining the architect’s aesthetic.