Mike Zuspan found his piece of the American dream in Roswell, near Ga. 400 and Holcomb Bridge Road. At least that’s what he thought five years ago when he bought his home on Worthington Hills Drive.

Now he surveys the “For Sale” and “For Rent” signs sprouting like weeds among the neighboring lawns and feels depressed.

“It feels like the community is dying,” he said.

Zuspan’s suburban neighborhood is one of more than 300 throughout metro Atlanta in which the concentration of vacant housing exceeds 10 percent — a level that raises red flags among those who study neighborhood dynamics.

According to a rough but commonly accepted benchmark, in a healthy neighborhood, no more than 5 percent or 6 percent of properties will be vacant at any given time. Vacancies of 8 percent to 10 percent are cause for concern. Anything higher can send a community into a downward spiral of falling home prices, neglect, abandonment, rising crime, health problems and yet more vacancies.

“Vacant properties, especially above some minimum number, are devastating for a neighborhood,” said Alan Mallach, a nonresident senior fellow at the Brookings Institution, a nonpartisan research institute. Those like Zuspan who remain, he said, are likely to suffer “an enormous loss of value, an enormous loss of wealth.”

Empty houses and apartments also translate into empty desks at local schools, empty tables at restaurants, empty aisles at stores and empty pews at churches. If any of those institutions fails, the neighborhood becomes less viable and the downward slide is likely to accelerate.

With a vacancy rate of 12.2 percent, Zuspan’s neighborhood is in far better shape than dozens of others where recently released U.S. Census figures show 20 percent, 30 percent, 40 percent or even 50 percent of the housing units empty.

Mapping the vacancies reveals a broad swath of concentrated vacancies south of I-20 — but none of metro Atlanta’s nine core counties is immune.

The causes vary. Some older urban neighborhoods have seen an exodus to the suburbs. Many low- and moderate-income areas took a major hit from foreclosures. Zuspan’s neighborhood had a high number of subprime loans. Shiny new exurbs may simply have overbuilt just before the recession hit. And few communities have escaped foreclosures caused by job losses.

Bearing the brunt

Areas with concentrations of apartment complexes can be hit particularly hard.

In Cobb County, for instance, some census tracts dominated by apartments have vacancy rates in excess of 23 percent, according to the census figures.

Brian Binzer, director of development services for the city of Marietta, said he finds those numbers hard to believe, but he acknowledged that at least one of the areas in question, along Franklin Road, was marked by several complexes that experienced foreclosure.

Binzer may doubt the census numbers, but some local merchants don’t. The owner of a check-cashing store said he’s lost almost half his business. A manager at the nearby Gantt Food Store also said business has slipped, perhaps 20 percent.

Just west of Smyrna, near Osborne High School, Mark Fraser lives in a complex that is about two-thirds vacant. Although that’s certainly bad news for the owner, Fraser, 51, says he is happy the place cleared out.

“There was a lot of drugs and violence,” he said. Things are quieter now, and Fraser is planning to start a community garden to build ties among residents.

Fraser’s experience is not typical. More commonly, crime rates and vacancy rates rise in tandem, according to those who study the issue.

Expert: Act quickly

For local governments, vacancies present a double whammy. They have to spend more to keep some neighborhoods from deteriorating even further; at the same time, they suffer a loss of property tax revenue to fund city services.

There are measures public officials can take to slow or reverse the deterioration, such as creating green space or establishing land banks to acquire abandoned properties and sell them to nonprofit developers, community groups or neighboring owners.

The important thing, said Mallach, of the Brookings Institution, is that communities must have a strategy — and act quickly.

“You’ve got to be proactive,” he said. Otherwise, “Things go downhill fast.”

The city of Roswell identified Zuspan’s neighborhood as a danger zone and snagged $721,000 in grants to rehabilitate six empty homes. Habitat for Humanity took on the renovations, and buyers are supposed to close on three of the houses in April.

Nevertheless, Zuspan is looking to sell and move away.

“It’s not going to make me want to stay,” he said. “I don’t think this neighborhood is coming back.”

Database specialist John Perry contributed to this report.

WHAT IT MEANS TO YOU

High vacancy rates have the potential to touch us all — and the implications go far beyond the real estate market. Yes, concentrations of vacant housing drain value from surrounding homes. But the growing problem also undermines local businesses, churches and schools, attracts crime and raises government’s costs. It also saps tax revenues.