This was the week of the DesignPhiladelphia festival, but you would have hardly known it in the granddaddy of design districts, South Fourth Street's Fabric Row. Foot traffic was light. There were no presentations on Big Topics, no signs touting glamorous parties with beer-sipping design types.

Instead, the business of cutting and selling cloth continued as usual. At Jack B. Fabrics, two generations of Blumenthals gathered on Friday afternoon around the shop's battered work table, the sole clearing in a thick forest of upright fabric bolts. A lone couple wandered the aisles of upholstery fabric, methodically fingering the material, but left empty-handed. Sherie Abrams busied herself by rewinding old bolts, while her father, and the store's namesake, Jack Blumenthal, dispensed fabric wisdom from his perch on a plastic cafe chair. The couple would be back, he predicted.

If business is slower than it once was, the Blumenthals and other third- and fourth-generation fabric merchants aren't complaining. They're just glad there is still a Fabric Row.

Like so many distinctive commercial districts in Philadelphia, Fabric Row is morphing into something new.

For generations, Philadelphians have gone to Fourth Street to acquire raw materials for bridal gowns, prom dresses, and furniture upholstery. But in the last few years, the surrounding area - once populated by Jewish immigrants who provided both Fabric Row's customers and workers - has been transformed by a new generation of middle-class homeowners. A wide range of new specialty shops have followed, filling storefronts that are still etched with the names of old fabric families: Kincus, Friedman, Goldberg, and Spivak.

Then, in April, a fast-moving fire swept through the original Jack B. store on the southwest corner of Fitzwater Street, causing the building to collapse and killing a veteran Philadelphia fire captain, Michael Goodwin. Retailers were stunned when a second blaze hit the block in August. It started in an upper-floor apartment, but shuttered Anh's Custom Tailors downstairs on the corner of Catharine Street.

The Blumenthals immediately reopened Jack B. across the street and began making plans to rebuild on their damaged lot. Anh's also is expected to return. Yet it is reasonable to wonder how much longer Fourth Street will be able to call itself Fabric Row.

Even before the one-two punch of the fires, which were both determined to be accidental, the industry's dominance was clearly waning. Since 2009, the percentage of stores between Bainbridge and Queen Streets - the boundaries of Fabric Row - that sell textiles and notions has dropped from 45 percent of the total to 28 percent, according to a new study by the Community Design Collaborative undertaken on behalf of the South Street Headhouse District. Today, it's just as easy to buy organic vegetables or a bike helmet on Fourth Street as a yard of good chenille.

All neighborhoods go through cycles, even if many lament the changes. "They used to call this South Philadelphia. Now it's Queen Village," marveled Rose Blumenthal, the third-generation owner of Jack B., and a cousin to the owners of B. Wilk and Maxie's Daughter, two of the street's most prominent retailers. "You hate to see a bicycle shop come in, but it's so much better than an empty storefront," she said.

The evolution of Fourth Street isn't much different from what is happening now to the city's other distinctive enclaves - from the Italian Market to the Gayborhood - where the conditions that once bound specific groups of people and businesses together no longer exist.

Of course, it's how change gets managed that matters.

In an effort to preserve Fabric Row's essential character, the Design Collaborative is putting the final touches on a plan for the street. It's a balancing act, aimed at stabilizing its traditional businesses while also encouraging new ones to continue locating in the district.

Those recommendations follow many of the familiar approaches for treating ailing commercial corridors: sidewalk extensions at the corners, better lighting, and strategic greening. But each idea has been crafted with the aim of "holding on to the Fabric Row brand," said Robin Kohles, who is overseeing the plan, which still requires funding from the city Commerce Department.

What that means is playing up the street's fabric heritage. The corner extensions would be paved in a "fabric pattern." Merchants are being encouraged to take down their security gates and install bright fabric awnings. Of course, there would be cloth banners announcing Fabric Row. They would hang from the street's old trolley poles, another vestige of its past.

Kohles acknowledges "there is something ironic in branding the street as Fabric Row when there is less and less fabric." But she and others still see a value in emphasizing the street's past. 

Even if the newcomers don't sell fabric, they often deal in related products, such as vintage clothing, noted Elena Brennan, a London transplant who founded Bus Stop, a shoe store. There also has been a mini-influx of tailor shops and upholsterers, including several owned by recent immigrants from Asia and Africa.

Judy Bucksbaum, whose grandparents founded Marmelstein's, also hopes that by improving the street's physical conditions, more fabric store owners will be inspired to modernize their businesses.

That's already happening. She stopped selling small stuff, like buttons and thread, to concentrate on high-end upholstery and drapery fabric. At Maxie's Daughter, Eric Trobman has created a side business providing upholstered banquettes to the city's restaurants.

Among the cluttered aisles of Jack B. Fabric, it might look like nothing has changed since the Blumenthals' grandparents started the business a century ago. But there is one innovation that isn't visible: They now have a webpage.

Changing Skyline: