In the world of New York real estate, prewar apartments are like double-edged swords. On one hand, they have the kind of classical details and structure that make interior designers’ imaginations go wild; on the other, there are few instances when a gut renovation isn’t the only course of action. So it was for a 3,000-square-foot beauty on Madison Square Park that checked all the right boxes—location, size, and a dreamy view overlooking the treetops—but was lacking the aesthetic one stylish family desired.

“The apartment was a mess: bad colors, bad finishes,” says celebrated interiors whisperer Ryan Korban, who converted the three-bedroom space from what he calls “suburban” into a classic Manhattan aerie that blends downtown chic with uptown elegance for repeat clients with their own design credentials (the husband is the founder and owner of luxury bedding brand Kassatex ). “Everything was brown; there were too many walls. It felt very heavy and closed in.” Using the floor-through apartment’s many windows as a framework, he opened up the space, knocking down partitions, installing discreet built-in storage, and establishing a family-friendly layout that separates public and private spaces; then transformed the residence with his signature brand of warm minimalism.

“The apartment is classic New York but also edgy and cool,” says Korban. “She tends to respond to more traditional things and he prefers things to be more clean and sexy.” A pair of pieces by Basquiat hang in a gray-hued hallway.

Working closely with the client, Korban established a palette of cool grays, creamy whites, and moody blacks, grounding the design in sleek urbanity while using plush texture to soften the look. “It’s good to have a client who knows where things should be,” he says. “He has a very clear vision of design and quality.” Metallic finishes contribute to the cosmopolitan vibe, not least in the kitchen, where polished chrome joins statuario marble—a fitting combination of contemporary and traditional elements—while suede, bouclé, and rough-hewn silks and velvets, particularly in the master bedroom, create a monochromatic cocooning effect. “I’m a firm believer in continuity and consistency,” says Korban, who recently released Ryan Korban: Interiors , with Rizzoli, of the understated undercurrent that runs throughout the home. “I don’t like too much variety.”

Of course, there are still moments of surprise, or what Korban calls the “wow factor,” which punctuate the restrained backdrop. A collection of colorful modern art by Basquiat and George Condo bursts against the apartment’s gray walls, and a small powder room becomes a showcase for high drama with gilded floral wallpaper and black finishes. “It’s sexy and masculine but still feminine and elegant,” he says. Much like the apartment itself, the contrasting elements create an aesthetic that feels appropriate for a modern family—and one that is undeniably New York.