The master bedroom of Schnabel’s duplex, with Picasso’s Femme au Chapeau. Photographs by Robert Polodori.

The artist Julian Schnabel is famous—too famous—for possessing such a big ego that he thinks he can do anything. The list of job titles attached to his name—painter, sculptor, furniture designer, filmmaker—keeps getting longer. But what if he really is that rare being, a true Renaissance man? The latest clue is a stop-you-in-your-tracks work of architecture he’s just now finishing up in Greenwich Village. Plunked smack on top of the early-20th-century factory building where the artist has long lived and worked on far West 11th Street is a Pompeii-red palazzo, stuccoed on the outside, with five huge residences, plus a studio for Schnabel, some serious exhibition space, and a swimming pool fit for Citizen Kane. The place looks as if it began life in Venice on the Grand Canal, somehow floated up the Hudson River, moored on the West Side Highway, then hoisted itself atop its three-story “pedestal.” The building even has a fanciful name, announced on its front: Palazzo Chupi, after the nickname of Schnabel’s Spanish wife, Olatz.

Incredibly, much of the construction and interior work, which went on for well over two years, was done while Schnabel was shooting and editing his latest film, The Diving Bell and the Butterfly, in Paris and Berck-sur-Mer, and then taking it on the film-festival circuit. At first, faxes with questions, comments, drawings, and images were sent from New York to the set, where Schnabel would work on this “side” project between takes, communicating mostly with Brian Kelly, a musician who started out as the artist’s assistant 25 years ago and who led the charge on the building in New York.

Construction had begun in September 2005, and, like a lot of Schnabel’s projects, it was initially controversial, drawing the ire of a Village preservation group, which staged protests. The cries of “there goes the neighborhood” hurt the artist, but they didn’t stop him. He said at the time, “In principle the protesters are right, but they’re wrong about me and this building.” (And he told his team to offer the demonstrators the use of his bathroom when the need arose.)

It’s not wrong to think of the whole 50,000-square-foot object—and that includes the original building, which has been completely reconfigured on the inside, as well as the new addition—as a huge sculpture designed for living. And that’s some living! With 180 generous windows, balconies galore with all kinds of spectacular cast-stone or bronze railings, and the largest terraces I’ve ever seen in this town, the building is one of a kind. Each of its residences—a triplex, two duplexes (one of which is occupied by Schnabel and his family), and two single-floor homes—has the larger-than-life quality that defines Schnabel himself. Everywhere one experiences pleasure in materials and the presence of the hand. One sees it on the walls, in how the plaster is applied; on the ceilings, with their unfinished timber; in the surfaces of the fireplaces, which are themselves sculptures. The sheer thickness of the walls—they range from one and a half feet to four feet—is monastery-like, and provides the same kind of quiet. Tiles are used abundantly and to fantastic effect: cement tiles from Morocco, clay ones from California, and handmade, terra-cotta tiles from North Carolina—all coexist as if they’d never been apart.

Within Palazzo Chupi, Schnabel has found an original way to reference and meld many of the architecture-related experiences that have affected him, informed him, and inspired him over the years. In fact, one could view the building itself as a sort of architectural autobiography. The grandness and craftsmanship betray the memory of a little boy who was nuts about his parents but felt debilitated by the small scale and lackluster materials in their Brooklyn home. “Everything was fake, except them,” he remembers. “It was the feeling of limitations.” (Neither of Schnabel’s parents are alive, but I’d still say this place is for them.) Then there’s the epiphany he had as a young artist walking through a huge wooden door into a courtyard in Mexico City and being wowed by the sense of privacy that people could have in the middle of a teeming urban world. That revelation is reflected in the interplay between indoor and outdoor spaces that is such a big part of Palazzo Chupi’s effect and in its no-holds-barred views of the Hudson River.

But the place that has had more influence than any other over Schnabel is the Scrovegni Chapel, filled with frescoes by Giotto, in Padua, Italy, which, when he first saw it in 1977, at the age of 25, led to his most important artistic epiphany. “It was the complete experience that I knew must have been there but I hadn’t seen before, where the architecture of the place and what was painted on it were inseparable,” he recalls. “What I came to understand there was that I needed my paintings to be walls. I needed to build an architecture to support whatever pictorial language I was going to invent.”

Of course, Schnabel’s West Village building is an entirely different kind of Gesamtkunstwerk, or total artwork, but it is born from the same fervent attitude that makes Giotto’s blue-backed frescoes so unforgettable. It also owes a huge debt, which Schnabel freely acknowledges, to two American architects: Addison Mizner and Stanford White. Schnabel’s experience with both architects’ work is personal and direct. He has rented a Mizner house in Florida in the past, and owns an 1880s fishing “cottage” by White in Montauk, on Long Island, where Schnabel spends lots of time painting and surfing. The West 11th Street building abounds in nods to both architects, all of them put through the Schnabel strainer. He’ll take a Mizner fireplace, for instance, and create a pumped-up version by, in his words, “putting some balls on it.” Likewise, the kitchens in each of the Chupi residences—with their board-and-batten wooden ceilings, emerald-green terra-cotta tiles, and cast-concrete countertops dyed chromium-oxide green—are straight out of Schnabel’s Montauk house, though re-tuned. None of this is simple mimicry. What’s interesting is how Schnabel mixes references to White and Mizner into a global iconography, including Moorish, Turkish, and Venetian touches, motifs the architects were attracted to themselves.

Palazzo Chupi’s ground-floor lobby.

In 1987, Schnabel was introduced to the original building—which in previous lives had been a stable, a perfume factory, and a water-sampling plant—by the artist Roy Lichtenstein. They’d run into each other and, as artists like to do, started talking real estate. Schnabel asked, “Did you find your dream loft?” “I did, but it’s too big for me—it’s right for you,” replied Lichtenstein, who knew his customer. At first Schnabel just rented some space for a studio, but after he split from his first wife, Jacqueline, he set up camp there in a womb-like cubicle he built in a mezzanine, just above the studio, which he called “the Monkey Room.” (The label was a nod to the stuffed simian residing within.) He covered the walls with red velvet, brought in a few favorite possessions, including Picasso’s Femme au Chapeau, ran The Godfather on his VCR 24 hours a day, and painted his way out of his hole, eventually remarrying, buying the building in 1997 for $2.1 million, and creating a home there for his family.

A few years ago, when Schnabel decided he needed more elbow room, he naturally thought he’d take advantage of his right to build on the roof. He started sketching out ideas, which evolved from a simple rooftop cottage to the deliciously bonkers notion of putting up a palazzo on the dour block. Soon it was time to bring in an architecture firm, Hut Sachs Studio, from New York, which figured out how to pull off Schnabel’s vision. Since then, the team responsible for the finished product has included a whole range of artisans and artists as well as the usual construction crews.

Now that it’s finished, Palazzo Chupi has gone from being a neighborhood pariah to a place that people point at and ooh and aah over. Isn’t that the way with art, when it’s good? First there’s the outrage, then comes the pedestal. We’ll see how it does in the marketplace. Bono, Johnny Depp, Martha Stewart, Hugh Jackman, and Madonna have all checked out the remaining residences for sale, at prices ranging from $27 million to $32 million. (Schnabel declines to reveal his overall construction costs.) So far two units have sold: a single-floor, for $15.5 million to Credit Suisse executive William J. B. Brady; and the other single-floor to Richard Gere for an undisclosed sum. There’s a funny anecdote about Madonna looking out at a neighboring Richard Meier apartment building on the West Side Highway. As the story goes, the singer remarked that its cool modernism reminded her of a housing project in comparison to Schnabel’s Venetian splendor.

Meanwhile, as his new film racks up awards and Oscar nominations for best director and adapted screenplay, Schnabel and his wife and 14-year-old twin sons, Cy and Olmo, have settled into life in Palazzo Chupi. Schnabel will have to accept the way each eventual buyer finishes up his or her place, but he has decorated his own home the way he always does—alive with color, full of art and surprises. A photograph by Luigi Ontani hangs above a massive “elephant leg” cast-stone fireplace in the living room, which also has works by Francis Picabia, Man Ray, and Schnabel himself. Here the walls progress from turquoise green to faded mint. In the master bedroom they’re fuchsia—which makes the intense greens of Picasso’s Femme au Chapeau look even more vibrant. Two of Schnabel’s greatest paintings, St. Sebastian and Procession for Jean Vigo, also hang in the bedroom, together for the first time in ages.

If you know Schnabel, one thing that’s fascinating about Palazzo Chupi is that it’s really just a big-time expression of an impulse he’s always had. For decades now, he has been rejiggering rooms he’s found himself in, from simple tweaks to total reconstructions. (His abilities in this arena have been public knowledge since the August 2006 opening of the newly renovated Gramercy Park Hotel, where Schnabel designed the public spaces as well as much of what went into them.) We’ve been friends since the early 80s, and I’ve witnessed this obsession with physical equanimity up close. Once, in the late 80s, we shared a hotel room in Florence, and when I checked in, I found he’d already moved the furniture around and taken down the standard-issue art reproductions, replacing them with some drawings that Cy Twombly had given him the day before. He wasn’t being cute; it was just something he needed to do. The chambermaid was horrified by the scribbles that had been scotch-taped up on the walls. Maybe Schnabel should send her a plane ticket so she can see Palazzo Chupi.

Ingrid Sischy is a Vanity Fair contributing editor.