When AD100 designer Julie Hillman first stepped into the grand 5,600-square-foot Park Avenue duplex, she recognized both the exceptional potential and the inherent constraints of its classic bones. The residence, belonging to a New York City couple with three children, offered a traditional and very proper layout: bedrooms situated upstairs, while the downstairs featured a living room, a dining room, and a library, each anchored by its own working fireplace. Rather than upending this time-tested spatial organization, Hillman chose to respect the apartment’s architecture while entirely reinterpreting its atmosphere, bringing together an extraordinary cast of international artisans to forge a sophisticated home tailored equally to lively social gatherings and intimate family life.
From the outset, the homeowners placed deep trust in Hillman’s vision. Reflecting on the partnership, one of the homeowners noted that from their very first conversation, it was clear the designer not only understood their goals but also possessed an extraordinary eye. To execute this comprehensive yet respectful renovation, Hillman collaborated closely with Ferguson & Shamamian Architects. While the original floor plan remained largely untouched, the design team did undertake one major structural alteration in the kitchen. By combining a former laundry room and an outdated bathroom, they carved out a spacious breakfast corner complete with a resized window. Tom McManus, the architect who led the project on behalf of Ferguson & Shamamian, explained that the goal was to open up the rear space, flood it with natural light, and give the apartment a much fresher feel—a key priority for the clients.
Hillman’s meticulous curation of the interior begins even before entering the main apartment, starting at the private elevator landing. Here, she commissioned a custom metal-and-glass front door inspired by sliding doors she had admired at the historic Villa Necchi Campiglio in Milan. Fabricated by artisan Neil Wainland, the geometric piece had to satisfy rigorous safety regulations while delicately balancing the transmission of light between the private vestibule and the interior beyond.
Passing through the entryway brings visitors into the home’s central gallery, where original marble floors were carefully preserved to establish an immediate dialogue between classic New York architecture and cutting-edge contemporary design. Tucked beneath the gallery’s curved staircase—which has been outfitted with sleek, contemporary railings—sits another striking geometric form: a 1940s pedestal table created by German sculptor Siegfried Pütz. Just nearby, an arched black door opens unexpectedly onto a daring powder room featuring textured black patchwork walls crafted by Mongiardo Studio, an ebony marble sink, an Isabelle Sicart mirror, a vintage Jean Perzel suspension lamp, and vintage gilded sconces by Hervé Van Der Straeten.
The theme of bespoke, highly tactile craftsmanship continues into the expansive living room, where Hillman designed seating arrangements to accommodate gatherings of vastly different scales. Whether the room hosts a lively party of twenty or a quiet conversation between two people, the furniture supports fluid movement and intimate pockets alike. On one side of the room, she paired a vintage Swedish wood-framed sofa with an André Arbus daybed featuring delicate glass feet, anchoring the grouping with a monumental bronze coffee table by Ingrid Donat and a painting by Richard Prince positioned above the mantel. On the opposite side, a series of rounder, more embracing sofas encircle a bespoke mirrored coffee table crafted by Sam Orlando Miller, complemented by vintage bronze-and-parchment sconces designed by Felix Agostini.
The dining room presented its own spatial challenges due to its generous proportions. Eager to avoid a layout that felt overly clinical or "like a conference room," Hillman commissioned Italian artisan Mauro Mori to create two distinct tables supported by robust sculptural pedestals. Equipped with hidden casters beneath their bases, the tables can be effortlessly pushed together for large dinner parties or separated as needed. This flexible arrangement is illuminated from above by an oversized, room-spanning chandelier commissioned from Milanese lighting company 6:AM, composed of clear and matte glass rendered in nuanced shades ranging from ochre to smoky gray. Nearby, a Keith Haring painting brought over from the clients’ previous home bridges the transition from the central gallery.
Hillman’s dedication to working with artisans who possess a distinct point of view is perhaps most vividly felt in the library. There, Anjou-based textile artist Anne Corbière hand-wove silvery-bronze metallic thread into custom fabric wall panels, creating a deeply tactile environment. This textured backdrop is paired with bronze coffee tables in a custom finish by Gloria Cortina and significant artwork by Richard Serra.
Upstairs, the transformation continues with the conversion of what was once a grand foyer into a relaxed, light-filled family room situated conveniently between the children’s bedrooms. Hillman designed a low, built-in sofa that hugs the perimeter of the room, anchoring the space around a sculptural pequi wood coffee table by Hugo Franca, alongside artwork by Paige Israel and Porfirio Gutiérrez.
In the primary suite, the pursuit of unique, character-driven pieces yielded serendipitous discoveries, including a 1910 secretary cabinet that Hillman came across by chance and immediately secured for the nearly 11-foot-high room. Crowning the piece with a sculptural ceramic vessel to balance its scale, she paired it with a bronze and crystal pendant by David Wiseman and low tables by Franck Evennou. The primary dressing room further showcases the extraordinary handiwork of Anne Corbière, who embroidered delicate cashmere for a series of closet doors, each deliberately crafted to be slightly unique from its neighbor. This zone also features a custom parchment desk by Simon Orrell and a striking selenite island designed by Hillman and fabricated by Nicolas Mongiardo. A secondary primary bathroom rounds out the private quarters with masculine stone accents, a steel-and-leather stool by Michael Boyer, and a cast bronze sconce by Hector Esrawe.
Reflecting on the multi-layered design process, which frequently involved intricate, multi-step artistic collaborations, Hillman acknowledges that the path was rarely simple. "I really love doing things that I haven’t seen before," she notes, recalling that the intricate fabrication cycles often prompted moments of reflection on whether they could have made things easier. Ultimately, however, the designer maintains that the rigorous journey was entirely worthwhile, resulting in a Park Avenue residence that stands as a deeply personal, uncompromising collaboration between visionary design and world-class craftsmanship.