On an October day in the Decatur, Ga. neighborhood of Oakhurst, the sounds of an R&B band share airspace with smoke from a barbecue trailer. A couple of blocks away, a jazz trio noodles on the front porch of a 1920s bungalow.

Organizer Scott Doyon, traveling through the neighborhood in fits and starts on a Vespa, just can't seem to find enough time to drink in even a fraction of Oakhurst Porchfest's 134 performers and talk to his neighbors.

Porchfest, founded in 2007 in Ithaca, New York, by Lesley Greene and Gretchen Hildreth, has since become a nationwide phenomenon. Similar fests now take place in San Francisco, Kansas City, Washington, D.C. and many other cities big and small.

The concept is simple: take a diverse hodgepodge of music artists and let them perform on front porches scattered throughout a walkable neighborhood, creating a daylong festival where fans can roam from band to band -- like a sonic bar crawl.

For Doyon, a principal with Placemakers, an urban-planning firm that's heavy on civic engagement, that smorgasbord of music is both the best and most nerve-wracking thing about the festival.

“It's the thing that makes it both applauded and critiqued," he says. “There's no chance in hell you'll catch anything more than a small fraction of what's available."

But the community-building feel of the event is palpable, even if arranging more than 130 bands in a square-mile swath without creating a cacophonous mess is a feat of extreme matchmaking, Doyon says.

“You have to get 130 people who say they'll host a porch and 130 bands who say they want to play -- all with different times they're available,” he adds.

Add to that the fact that louder bands must be placed a respectful distance from folk singers in order to keep the peace.

This year, a bagpipe band crashed Ithaca's Porchfest, missing the memo that performers must sign up in advance to get the gig. An overabundance of unscheduled performers can create sonic soup, says Ithaca organizer Andy Adelewitz.

“The bagpipe people were very apologetic," he explains. “But that's the kind of thing that can happen, where you have a full band playing across the street from an acoustic duo."

That seems to be the only rub when a good idea like Porchfest catches fire — that and a newfound need for street closures and other safety measures, now that thousands come to hear and be heard.

“It keeps growing organically on its own," Adelewitz says. “At this point, it's just about figuring out whether there's a limit to the logistics of scheduling 20 more bands every year."

The Winnona Park Elementary Community Circle Band performs at Oakhurst Porchfest.

Photo Credit: Greg Wiseman

Despite the numbers, the crowd self-manages, dividing itself into “pockets of interest" throughout the neighborhood, with most bands attracting audiences of no more than 20, Adelewitz explains. “It still feels very small and intimate to us,” he adds, “and it really is about neighbors playing for neighbors and neighbors watching neighbors play."

Though organizers have made tweaks including adding temporary toilets and food truck parks, Porchfest remains a nonprofit, mostly revenue-free festival, where private homes play host to entertainers.

Given the event’s homegrown appeal, which turns the crowded and commercial modern-day festival on its ear, its growing popularity is not surprising. But from Montreal to San Francisco, each Porchfest neighborhood has its similarities, Adelewitz says.

“In a lot of cities, you find that there's a neighborhood that's a creative hub to one degree or another,” he said. “There's a can-do spirit and a celebration of community and creativity that goes on in those neighborhoods."

Rob Steuteville, a writer and editor in the field of new urbanism and a musician who has played Ithaca's Porchfest every year, says the festival can only thrive in walkable neighborhoods.

“I think that an event like Porchfest brings out a sense of community which is made possible to a degree by the physical form of the community," he explains. “I don't think this type of event would have ever happened in a new subdivision."

Therein lies its appeal, says Kansas City Porchfest organizer Kathryn Golden, who discovered Napa Valley's version while living in California. “I thought it was an amazing community-building event," she says. "I think it feeds that whole sense of this is a great space and a cool place to live."

With Kansas City's legacy of jazz, growing folk scene and burgeoning rock movement, Porchfest's patchwork of sound appealed immediately to locals, quickly outgrowing its original setting.

Golden is eying the historic Northeast district for 2016, an artsy community where long-neglected homes are being restored to their former grandeur.

“It has undergone a resurgence, but for people who have been here a long time, I think there's still this sense of, is that area safe?" Golden says.

The first two Porchfests, held in the West Plaza neighborhood, inspired a flurry of cleanup in the area. The neighborhood, ready for its close-up, drew plenty of media attention. Golden expects the same thing to happen for the Northeast neighborhood, bringing into focus the district's renaissance and walkable livability.

“I think there's some value in Porchfest beyond just people playing and hearing music," she says. "There's a culture I love being a part of."

Oakhurst's Doyon agrees.

Like many other walkable, older neighborhoods, Oakhurst is experiencing gentrification and the conflicts between newcomers and old-timers that often come with it.

But he thinks events like Porchfest can go a long way toward creating a united front in growing neighborhoods.

“There's a lot of research and data that makes clear that, the more connected and interdependent communities are, the better they can weather change," he says. “I'm certainly not under any delusion that a music festival can save the world, but the more we can start kicking down those divides between people who don't know each other, and get people interacting as neighbors, the more they'll take care of each other."