Loudoun County's first permanent shelter for the homeless won't open as scheduled this year and is in danger of not being completed, in part because many construction firms that volunteered supplies or services can't meet their commitments, project organizers say.

The $750,000 project, proposed by the region's development community, is apparently unprecedented in the Washington area. Originally scheduled for opening a year ago and later slated for use this winter, it has been delayed by design changes, site problems and the poor financial health of many of the companies that during stronger economic times had promised help.

Organizers hope for a new infusion of money and other support that would complete the building in March. "We're just struggling right now," said project coordinator Bruce DeAtley, vice president of Intergate Investment Builders. DeAtley and others say the volunteer effort should be adequate to get the building's shell erected. But interior work, such as plumbing and wiring, hinges on more donations from the already hurting construction industry and money from the county government, they say.

For Loudoun's homeless population, the delay means another winter of shuttling among government-financed motel rooms and small shelters run by a private, church-funded group. "Obviously it's just a Band-Aid approach. We plan and hope to do more," said county Social Services Director Carmen Nazario.

Estimates of those with inadequate shelter in Loudoun range as high as several hundred -- many of them local families with one or two working adults. Authorities say the phenomenon reflects a larger problem of an acute shortage of low-cost housing in the county, which stretches from Dulles International Airport to the West Virginia border.

The Loudoun homeless shelter, under construction just south of Leesburg, would house about 40 people and would be geared more for "transitional" housing of up to a year than for emergency shelter. The facility would help families and single women learn job skills and obtain permanent homes. It is to be run by a nonprofit organization, with operating funds coming from the county government and the U.S. Department of Housing and Urban Development.

More than 50 companies pledged services, supplies or money to build the shelter, but only about 35 have come through, according to Lynn Bays, whose McLean-based firm of Jack Bays Inc. is acting as the project's general contractor.

Some of the subcontractors have gone out of business, and several "just said they can't afford to do it," said Bays. "We just lost the guy pouring the {concrete foundation} slab," said DeAtley. "He's owed $400,000" by clients. Loudoun officials, who provided the land on which the shelter is being built, have not said whether they would bail out the project with construction funds. "We haven't reached that point yet," said Assistant County Administrator Russell Blackburn.

The 60 beds in four houses operated by the private Loudoun County Emergency Housing Alliance are near capacity much of the time. "We get calls daily from people wanting in," said the Rev. Charlie Grant, who heads the alliance.