Fans of the Bravo reality TV series “Project Runway” will likely remember when contestant Christian Siriano took the show’s host, Tim Gunn, on a tour of the tiny East Village apartment where he lived and worked. Now that Mr. Siriano has won the show, the designer has ditched his shared one-bedroom apartment in favor of a newly renovated 1,400-square-foot loft in Williamsburg.

Mr. Siriano, 22, said he wasn’t specifically looking to rent in the trendy Brooklyn neighborhood, and would have been happy to relocate to Chelsea or somewhere else in downtown Manhattan. Being from Annapolis, Md., though, he said he appreciated that in Williamsburg he could live by the waterfront. He also fits in well with the neighborhood’s young, fashion-forward residents.

“There’s a great little park around here that’s like a mini Central Park,” he said. “On the weekends it’s just full of fabulous-looking people on their fabulous bikes,” he said.

Mr. Siriano said he was at first turned off by his building’s old, graffiti-covered exterior, but as soon as he saw the inside of the apartment he knew it had to be his. When he moved in three weeks ago, he was the first person on his floor.

The open space features an entire wall of windows that creates a constant stream of light, and a sunken living/dining/kitchen/work area. The apartment’s appliances are brand new and stainless-steel (though Mr. Siriano admits he doesn’t cook much), and slate countertops and slate bathroom walls add to the modern, clean look of the place. He also loved the floors. “They’re concrete and acid-stained. Aren’t they fabulous?” he said.

Mr. Siriano, who’s become something of a pop-culture icon thanks to a large personality, frequent use of the words “fierce” and “ferosh” (short for ferocious), and a predilection for catchphrases such as “hot tranny mess,” has gone from freelance makeup artist to bona fide celebrity designer.

He has sold his clothing to “Project Runway” judge Heidi Klum and former Spice Girl Victoria Beckham. Next up, he’ll design an outfit for Whoopi Goldberg to wear while she hosts the Tony Awards. He plans to do it all from his new loft.

“I needed to find a space that was big enough for me to work and live in,” he said. “Right now my work is my life, and I might as well do everything in one place. Studios in New York are so expensive and they’re so small, so I thought, I might as well get two for the price of one.”

Mr. Siriano’s professional evolution is evident in his work space, where the small table he used while designing his winning “Project Runway” collection sits dwarfed by a new, 8-foot-long table — something that never would have fit in his old place.

In the work area, a shelving unit is filled with fabrics of all kinds and colors. On a rack nearby hang some of the bold, edgy, and modern designs for which Mr. Siriano is known — including pieces from his “Project Runway” collection, the dress he showed during his audition for the series, and the shirt he recently wore to the “Sex and the City: The Movie” premiere.

On dress forms next to his design table are two of Mr. Siriano’s most recent works: a skirt he designed for his “Project Runway” model to wear to the “Sex and the City” premiere, and a dress featured during his guest-starring stint on the ABC series “Ugly Betty.” Nearby is one of his proudest achievements: the oversize $100,000 check he received from Bravo.

A self-proclaimed neat freak, Mr. Siriano’s hats and shoes are displayed in perfectly organized rows on top of his work tables. Next to his bed, a large collection of sneakers is meticulously lined up, and on his coffee table, fashion magazines are stacked neatly.

When he moved into his new place, he brought just two pieces of furniture (his old design table and the shelf unit), so he’s now in the process of buying more. So far, he’s bought pieces from CB2, Design Within Reach, and Z Gallerie, all with a very clean, minimalist look.

The apartment’s white walls are almost entirely bare, but Mr. Siriano plans to create his own art to hang. “I need to have color,” he said. “I like abstract art, and I plan to buy some big canvases and just go crazy. I really love three-dimensional art, so I want to find some cool stuff and put it on there,” he said.

Much of his art incorporates found objects. On his design table stand two Union Jack paintings he scored on the street and painted over. These particular pieces appealed to Mr. Siriano in part because he spent three years in design school in London.

The apartment’s raised entrance area, which Mr. Siriano plans to turn into a gallery, features an oversize frame covered in mirrored paper that he found outside his apartment — a dramatic piece that is clearly the work of a designer who sees potential in everything that’s around him.

For Mr. Siriano, fashion and design are everywhere. In fact, on top of his kitchen’s slate countertop stand a series of vintage Vogue covers, which he said helped provide inspiration for the 1920s-style costumes he’s doing for an upcoming movie.

With a busy schedule that also includes working on a book (with his illustrations, quotations from celebrities, and tips on how to look “fierce and fabulous”), acting as a red-carpet judge for MTV, and designing for personal clients as well as Bluefly.com and Puma, Mr. Siriano might just wear himself out.

Luckily, he has lots of places to rest his weary head, including a modern rendition of a Ludwig Mies van der Rohe Pavilion design, called a “Barcelona Daybed,” a Design Within Reach sofa bed, and a large bed given as a gift by W Hotels. For a man who used to sleep on a mattress on the floor of his apartment, that’s not bad. “My mom was here the other day and she jokingly said, ‘Wow, Christian, you’ve gone from having no beds to having three,'” he said.