Developer Sioni Group, founded by brothers Ray and Jack Yadidi, along with their partners AB & Sons, announce that their 70-story curvilinear tower, formerly referred to by its address, 989 Sixth Avenue, will now be known as Casoni. The name of the distinctive new residential building rising in the Midtown-Bryant Park neighborhood is inspired by the Italian word “casone,” used for grand villas of high style, craftsmanship, and timeless sophistication.
Casoni has a host of innovations, ranging from unique and mindful ways to deal with structural and aesthetic elements such as weather and wind, glass, lighting, and heating and cooling, in addition to intricate code requirements. Through their collaboration with Dan Sehic, AIA, of C3D Architecture, Sioni’s core tenets of sustainability and technical innovations for the project were met. Casoni will be the tallest residential building in Midtown-Bryant Park with 311 apartments, the largest number of ground-up new development units in the area.
What truly distinguishes the tower is its sweeping champagne-colored curved wall system, made possible by the freedom of a corner lot. The building’s facade incorporates a dynamic mix of high-performing glass, aluminum panels and precision metal cladding — all engineered in Europe using modular techniques to ensure both aesthetic cohesion and technical excellence. Continuing to soften the lines of the structure, curved balconies follow along the northeast corner and at the top of the building to offer residents a seamless blend of indoor-outdoor living. These balconies also improve airflow and wind-load performance. The resulting cylindrical form is a rarity in Manhattan.
The team integrated bird-friendly reflective glass into the design and engineered the façade, of over 300,000 square feet of curtain wall, to withstand extreme wind loads. Toronto-based Motioneering, a world leader in control solutions, pre-tested the structure for hurricane resilience with up to 150 miles per hour winds. Further performance testing took place during the glass production at a specialized facility in Europe.
Unique exterior lighting was woven deeply into the architectural narrative as well. “After 18-months of intensive development, Sioni collaborated closely with facade manufacturers, structural engineers, the design architect and lighting consultants to create sleek, vertical linear fixtures, discreetly integrated into the exterior recesses,” explained Ray Yadidi, of Sioni. “Creating a living rhythm that animates the building from sunrise into nightfall, sensors adjust the brightness in response to natural light rhythm.”
The tower’s mechanical systems presented a challenging opportunity for more technical creativity. Sehic explained the heating and cooling required exterior louvers which could have disrupted the sleek appearance of the glass curtain wall. A solution was devised as Sioni Group worked with Masha Dinaburg, P.E., LEED A.P., Associate Principal at MGE and her Mechanical Engineering team, the Structural Engineering team with Ryan Dow from McNamara Salvia, and C3D Architects, which resulted in the first-of-its-kind approach that allows the building to maintain an uninterrupted glass aesthetic without compromising code compliance or functionality.
Casoni will be the first residential building in New York City to deliver this level of integration – where lighting, mechanical systems, and architectural form become a unified expression in concealed mechanical louvers.
Sehic stated, “Our approach with Casoni was to embrace every constraint—whether wind, mechanical or zoning — as an opportunity for creativity. The cylindrical form, the integrated louvers for fresh air and exhaust, the dialogue with the landmarked Gotham Hall next door — every decision leaned into finding harmony between form and function, past and future.”
Designing a modern tower adjacent to the neo-classical Roman landmark Gotham Hall — a structure known for its symmetry and grandeur– Casoni introduces a bold counterpoint: a sculptural podium with soft, organic lines. Each floor of the podium subtly protrudes outward by one foot, both vertically and horizontally. The structural custom clear-glass podium seems to have a movement of its own as it rises to the first set-back at the ninth floor – the same height as Gotham Hall. Leaning slightly in the direction of this landmark, it is a respectful architectural dialogue between past and present.
The interiors will showcase stately stonework, millwork, and smart-home features. The design incorporates open terraces at the rooftop and on the 23rd and 58th floors. Additionally, there will be over 25,000 square feet of amenities with two floors dedicated to wellness and fitness.
The crystalline curved tower is located in an area renowned for its connection to fashion. Louis Adler, Co-CEO and Founder of REAL New York, stated, “The developer sought to honor the neighborhood’s iconic style history in a way that projects graceful, international elegance to the affluent residents who will call Casoni home. This tower, by virtue of its height, vertical illumination, and curving silhouette, will hold a prominent place in the city skyline.” Adler continues, “Sioni is a deeply-rooted, family-operated company, with relatives working across all divisions. That personal investment is evident in every project they undertake.”
The building is set to open in 2026. https://casoninyc.com/
