520 West 20th

85,000 square feet
7 stories
New York, New York
2021

Located just off the High Line, this new office building incorporates an existing brick structure that is one of the few remaining vestiges of Chelsea’s industrial past. Rather than compete with the high-profile architectural spectacles that have transformed the renowned art district, the original warehouse was rehabilitated as a reminder of the neighborhood’s history. However, hovering above it, a cantilevered addition reflects more contemporary values to bridge the past and the present.

Aerial view at sunset of 520 West 20th, its dark glass and steel addition cantilevered above the original red brick Chelsea warehouse

The original warehouse, more recently used as a parking garage, was barely altered by the design team. Its exterior was preserved exactly as found, with patches of discolored brick and faded advertisements left intact.

Inside, the generous ceiling heights of the original building remain, as do the original concrete, brick and timber elements that imbue the office space with warmth and historic resonance. These same materials reappear in the new lobby, alongside board-formed concrete walls. A custom reception desk and large feature wall inspired by the work of Carl Andre, built using repurposed railroad ties that recall the nearby High Line, instill in the lobby an artistic sensibility fitting the gallery-dense neighborhood. Also found on the ground floor is neighborhood-oriented gallery space.

The historic integrity of the warehouse is preserved with the help of two new vertical cores that support the glass and steel addition. Derived from car elevators that once anchored the building’s east and west sides, these cores carry vertical circulation and mechanical systems through both structures, emerging like masts to support the glass and steel box spanning between them.

The stark contrast between the building’s two primary components is reinforced by the cantilever of the addition, which appears to float above the warehouse. The glass and steel overbuild offers contemporary, minimal office spaces that contrast with the warmer spaces inside the preserved warehouse.

Corner of the glass and steel addition projecting over the brick warehouse below, with a view down West 20th Street toward the Hudson River at dusk

Aerial view of the preserved brick warehouse with the dark glass and steel addition above it, and a planted rooftop terrace between the two cores

The lobby features a custom reception desk and a large feature wall that was inspired by the linear- and grid-format sculptural work of Carl Andre. These details intentionally instill an artistic sensibility fitting the gallery district.

Lobby with a reception desk and tall feature wall built from repurposed railroad ties, set against gray concrete and painted white brick

Rendering of an office floor in the glass and steel addition, with diagonal steel bracing at the windows, a wood ceiling, and a suspended planter

Rendering of an open office in the original warehouse, with concrete columns, dark steel beams, long shared desks, and a lounge area

Floor plans for 520 West 20th Street- a glass and steel addition above a preserved Chelsea warehouse in New York

Top: Typical plan, floors 6 and 7. In the glass and steel addition, the building’s two vertical cores help structure 520 West 20th Street’s open, flexible office spaces along with housing vertical circulation and mechanical systems. Middle: Floor 5. The single-story glass-enclosed volume between the original building and the bridgelike addition accommodates various uses and features a wraparound, landscaped terrace. Bottom: Floor 2. A typical office arrangement in the original brick building.

On the roof, the building’s mechanical equipment was incorporated into the design of the landscaped terrace. Perforated metal screens surround the two vertical cores.