Loudoun County supervisors are considering getting rid of a development option that was designed to preserve open space but that some say encourages too much construction.

Supervisors are considering a moratorium on new zoning approvals for "rural villages" -- houses clustered close to one another on big swaths of rural land. The measure would apply everywhere except in an area along the western portion of the Dulles Greenway and a section of Dulles South.

The village concept, originally approved by the previous Board of Supervisors, was designed to allow developers to group houses and businesses on one portion of a property and preserve open space on the rest. The villages can be approved only on parcels of at least 300 acres on which zoning originally allowed one house on every three acres.

As an incentive for developers to preserve open space, the rural village zoning designation allows more houses than would have been allowed under the original zoning. But now some supervisors are expressing displeasure with those extra houses.

"Some of us out here have had concerns that the rural village was really turning out to be a town in competition with our little towns and was actually much more dense," said Supervisor Eleanore C. Towe (D-Blue Ridge).

But supporters of the village concept said they are a necessary method of discouraging sprawling developments.

"The whole point of developing it was to create an ability to preserve open space," said John A. Andrews II, president of the Loudoun chapter of the Northern Virginia Building Industry Association. "In order to preserve open space, there had to be some trade-offs. . . . It leads me back to ask whether the vision we want to have of the county 50 years down the road is just all grid A-3 or have little villages surrounded by open space."

The board sent the moratorium proposal back to committee yesterday to see whether the wording of the ban could be changed to prevent the county from accepting applications for new villages. The proposed wording had said that the county would not approve any new villages.

Board Chairman Dale Polen Myers (R-At large) said that refusing to accept applications would buy the county time to study the concept. She said that newly elected supervisors, who will take office in January, would not be bound by the current board's decision and that county staff likely would not be able to analyze the issue until next year.

Myers said that if a developer puts in a village application now, it could be considered soon after the new board takes office. If the board stops accepting new applications, it would give county staff more time to look at the issue.

So far, only three developers have obtained permission to build rural villages, and no houses have been built on those properties. In addition, county planning officials said no developers have indicated that they plan to file applications to build villages in the near future.

The villages already approved are: Courtland Farm, which allows 281 houses clustered on 818 acres on Route 15 south of Leesburg; Woodland Village, which allows 223 houses on 424 acres east of Watson; and Elysian Heights, which allows 312 houses on 1,303 acres north of Leesburg. Those projects would not be affected by supervisors' action.

Supervisor Scott K. York (R-Sterling) said: "The concept is a good one -- to preserve the open space. But people are concerned about the impacts on the infrastructure with the bonus densities in there."

The villages are a larger version of "rural hamlets" in which houses are clustered in smaller groups. Unlike with villages, developers of hamlets are not allowed to build more than the zoning would otherwise allow.