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Single Family Ultra-Luxury Apartment

Central Park West

Manhattan, NY

11,000 sf



The Owners approached us to design a large apartment on top of their six story 1930s apartment building. From the roof they had a cherished, though very slight, Central Park view; a key part of their rationale for the project.


After much study, we developed a unique and unexpected approach for an addition that emerges from one of the existing building courtyards, rising to 185’ and cantilevering out like a periscope toward the higher unobstructed park views. It was our zoning and building code experience combined with our creative approach that led to this solution, overcoming many real obstacles.


The design was developed as a ‘glass brownstone in the sky’. It starts with a private street entrance and virtual doorman services. The elevator and all essential services rise to the apartment in a carefully designed compact ‘shaft’. Inside the apartment is wrapped by curtain wall glass on all sides, with balconies and a rooftop garden to enjoy the 360-degree views. A slight twist in the plan on each floor creates subtly distinct views throughout the residence.


The residential addition the Owner wanted was to sit atop of an Old Code building that slightly exceeded the maximum allowed lot coverage. This limited any new construction to the existing building’s inefficient ‘dumbbell’ shaped floor plan, and structural considerations limited it to a few floors.


Despite these limiting factors, our analysis showed that the site had lots of unused floor area, a 185’ height limit and it sat just outside the neighboring Landmarks district. The building between ours and Central Park was taller but still well below the 185’ height limit. Critically, it was an overbuilt co-op, as unlikely as any to have a future addition on top. Our site had the unimpeded park views our clients wanted at the top of our zoning envelope. If only we could get there.


After a careful code study, and working with Expeditors and the Department of Buildings, we obtained five Commissioner Determinations to allow us to infill one of the existing courtyards, rise up to 185’ and cantilever over the existing structure below. The determinations also secured approval for other measures that made the project feasible. The addition was designed as a ‘stick’ built construction system to address the NYC Code prohibition on using cranes over occupied residences. The high cost of construction was readily surpassed by the higher value of the product created.

Periscope Case Study
CASE STUDY: Unexpected
Opportunities in the Codes
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