Houses in Ashburn’s One Loudoun development. How much does adding new homes cost the county? (Photo by Sarah L. Voisin/The Washington Post)

Since the recession, developers and landowners in Loudoun County — sometimes dubbed America’s wealthiest county — have repeatedly asked for approval to add hundreds of additional residential units to their properties, only to be turned away.

The oft-cited reason is that for every new home Loudoun adds, it commits to paying $1.62 in services for every dollar in revenue it receives, according to a 2011 study.

But after watching county officials cite the number in rejecting a string of zoning requests, developers, realtors, zoning attorneys and other real estate businesses are taking issue with the $1.62 figure.

The companies created a new organization, called All-In Loudoun, and commissioned their own study. Performed by the research firm Robert Charles Lesser & Co., the 29-page report argues that housing on average only costs the county $1.20 in services for every dollar it brings in.

Additionally, by allowing construction of more condominiums or higher-priced homes, the study argues, the county could break even.

Andrew A. Painter, a land use attorney with Walsh, Colucci, Lubeley & Walsh, P.C. who is part of All-In Loudoun, said the purpose of the study wasn’t to advocate for more housing construction in the rural west of the county or the “transition area” that cuts through the center, but to correct information from a 2011 study that he said was based on questionable methodology.

“This study doesn’t go to whether more growth is good or whether we should be opening the rural west and the transition area, or what have you,” Painter said. “It’s about figuring out what really is the number.”

Painter said the $1.62 figure had been used to vilify home builders. He said in one meeting with an elected leader — whom he declined to name — the official tossed the report across the table and accused the research firm of “cooking the books.”

“We’re trying to provide housing. We’re trying to meet a demand. Why is it that people look at us like we’re trying to rape and pillage the earth?” Painter said.

Among the companies that have failed to win approval for more residential units in recent years are the developers of the Greens at Willowsford, located near Prince William County south of Braddock Road, and Pulte Homes, which proposed re-zoning commercial land north of Route 7 in Ashburn for construction of town homes.

Another zoning attorney, Colleen P. Gillis of Cooley LLP, said she’s had similar difficulty getting new housing approved.

“The reaction very frequently has been we don’t want to approve this because all sorts of bad things financial and otherwise will happen,” she said.

The developers’ study came up with a lower negative cost for new housing in part by attributing 70 percent of sales and use taxes collected by the county to the presence of housing, rather than the shops themselves. Leonard Bogorad, managing director at Robert Charles Lesser & Co, said that distribution was appropriate because much of the county’s retail relies on purchases from county residents.

Christopher B. Leinberger, a land-use strategist who once co-owned Robert Charles Lesser & Co, said the methodology used to get to $1.20 was appropriate. But he said the critical take-away for Loudoun leaders ought to be that all types of housing are not the same.

Single-family homes in locations that always require driving are likely to create economic losses — partly from the added traffic congestion, Leinberger said — while densely built housing in walkable areas near the county’s planned Metro stations can create real estate value the county can then tax.

“The bottom line is still, single family housing does not pay for itself. Whether it’s a 60 percent loss or a 20 percent loss, it’s not paying for itself” Leinberger said.

Land use has long been a contentious issue in Loudoun County. In recent years, elected leaders have focused on adding data centers and office buildings to grow the tax base without creating additional need for school seats and other services.

Loudoun County Board Chairman Scott K. York (R) said he hadn’t closely reviewed the new study but that “since I’ve been on the board of supervisors most of the folks have been using the $1.60 figure.” (He was first elected in 1995.)

York said the cost of sending a child to school for a year, about $12,500, remained the largest expense of adding housing.

“You take a household that doesn’t have a student in there and it’s a net positive for the tax base so really it comes down to the number of children in that household that are going to school. It depends on the type of household we’re talking about,” he said.

Supervisor Matthew F. Letourneau (R-Dulles) said recent development projects have housed more students than expected, creating a “crisis in our budget planning process.” He and York both said they expect the county to re-visit its development blueprint called a comprehensive plan next year.

“What we’re finding in the new developments and in the popular places in the county like Brambleton and places in the Dulles South area, is those places are delivering more students than we had previously anticipated,” he said.

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