New York, NY

Completion Date: Fall 2011

Owner: 23 High Line LLC


Program: A 14-story, 39,200-square-foot condominium tower that extends above the High Line, an elevated public park built on a derelict railroad track that runs along Manhattan's West Side. The building, which has a concrete substructure and a steel superstructure, spans only 40 by 99 feet at its base. Slated for completion in fall 2011, the project includes nine full-floor residences, a duplex penthouse, and a ground-floor maisonette with a private garden. 

Design concept and solution: Working on a narrow site, the architects wanted to find a way for HL23 to fit snugly and naturally into its surroundings yet also stand out as a landmark on the High Line. To capture the most floor area possible, they adjusted the silhouette of the building to contract and expand according to site constraints and zoning regulations. Where the High Line meets the HL23's south facade, they bent the curtain wall inward and pushed out the east facade to regain lost square footage. Opting for a what-you-see-is-what-you-get approach, the architects drew attention to the steel structure: white-painted steel pipes cross behind the curtain walls of the north and south facades, echoed by a white ceramic frit pattern on the surface of the glass. The east facade, which directly overlooks the High Line, takes a cue from the park itself. Like a kind of overgrown stainless steel stalk, this facade is composed of paneling embossed with a subtly wavy pattern inspired by the textures of the plant life below. To give residents privacy without interrupting the facades, the architects chose motorized shades, along with blackout shades for the master bedrooms. Designer Thomas Juul-Hansen reinforced their minimalist approach with painted gypsum-board walls, wood floors for the residences, and terrazzo for public areas.

515–517 West 23rd Street, New York, NY


Owner: 23 High Line LLC

Neil M Denari Architects
TEL +1 310 390 3033
FAX +1 310 390 9810

Personnel in architect's firm who should receive special credit:
Principal: Neil M Denari

Project Leaders: Stefano Paiocchi, Duks Koschitz

Design Team: Carmen Cham, Alexander Janowsky, Philipp Traxler, David Aguilo, Antonio Torres, Breanna Carlson, Joe Willendra, Christian Kotzamanis, Yoichiro Mizuno, Rick Michod

Senior Designer and Site Representative: David Aguilo 

Collaborating architect(s): Marc Rosenbaum

Interior designer: Thomas Juul-Hansen LLC, New York

Engineer(s): Desimone Consulting Engineers

Lighting: LDA, Los Angeles

Rinze Van Brug

Neil M Denari Architects



Steel Structure
Breton Steel
500 Sagard Street,
Quebec Canada J3V 6C2

Glass Curtain Wall Megapanels
Sanxin Facade Technology Ltd.
Huizhou Dayawan Economic and Technological Development Zone, Shihuadadaoxi
Guang Dong, China  516081

Facade Consultants
Michael Min Ra and Bruce Nichol (partners), Jeffrey Kock, Jonathan Chin, Evan Levelle, Koshi Kawakami, Ben Bradley, Zack Wagand, Kyounghee Kim

Glazing Contractor


Glass Manufacturer
SanXin Glass Technology Co.,LTD.
17/F,Xinbaohui Building, Nanyoui.Road Nanshan district
shenzhen, China  518054

Stamped Stainless Steel Panels
Castro Barros 525/33
C1217 ABA Buenos Aires,

Aluminum Panels
Guilform Limited
Excelsior House
Wyncolls Road
Severalls Industrial Park

Motorized Glass Sliders at Penthouse
Capoferri Serramenti
via Cividini, 20
24060 Adrara  (S.M. (Bg))

Stud frame Megapanels fabricator and CW Installer
International Exterior Fabricators
4062 Grumman Boulevard Bldg. 81
Calverton, NY 11933

Otis Elevator Co.
1331 S. Curry Pike
Bloomington, IN 47403

Façade Access
Tractel Ltd.
1615 Warden Avenue
Scarborough, ON M1R 2T3