In a new flare-up of a long-smouldering conflict between District residents and hotel developers, Foggy Bottom dwellers are protesting an unusual time-sharing condominium being built in their West End community.

The gripes are about the soon-to-be completed Barclay House at the corner of 25th and K streets NW. The builder of the $3.5 million "post-modern"-style structure planned it as a luxury condominium but, faced with a sickly housing market, sold the nine-story building to Jim Locke of Barclay Properties Inc. for conversion to an "interval-ownership" apartment house.

Locke wants to sell the building's 26 rooms in one-week segments to upwards of 1,300 persons who, he contends, would save money by buying rather than renting their lodging. The plan is similar to that of the more common shared-time condominiums found in some resort communities.

Locke said to his knowledge the Barclay is the only building in an East Coast urban area with such a plan but noted there are several such facilities in San Francisco.

Barclay House neighbors, who have for several years protested the encroachment of hotels on their residential area, call the project a "hybrid hotel." They contend that the shared-time concept violates the spirit if not the letter of recent District rulings prohibiting hotel development in residential areas.

Zoning officials say Barclay House is defined as an apartment building rather than a hotel because its residents actually will own their rooms during the time they use them.

Barclay House neighbors feel this attitude puts technicality over reality.

"It smells like a hotel, it walks like a hotel -- it must be a hotel," says Nancy Kiefer, president of the unit owners' association in the Swarthmore condominium at 1010 25th St. NW, just north of the new building.

"We feel that the Barclay House is getting around the law and that it is really another hotel -- and another hotel is the last thing we need," said Jenny Brake, leader of the tenant's association in the Bader condominium, which adjoins the Barclay. Brake and others say the Barclay project will create traffic, parking and noise problems as short-term guests come and go.

Saying nearly 1,000 Foggy Bottom and West End apartment units have been converted to hotels or "hotel-like structures" in the past several years, Jon Nowick, chairman of the area's Advisory Neighborhood Commission, contends that a time-shared apartment "undermines the fabric of a residential neighborhood."

Although surprised and slightly embarrassed by the opposition, Sigal and Locke defend their decisions.

Sigal, president of Sigal Development Corp., said Locke contacted her and asked her if she would sell him the building for his interval-ownership plan. Because high interest rates made the future bleak for condominium sales, Sigal said, she agreed to sell. She makes no apologies for her decision and says the Barclay will enhance the community.

"We went out of our way not to put up a box," Sigal said. Barclay House replaced a boarded up small grocery store and a two-story town house.

Pointing out the car-choked Whitehurst Freeway, which feeds into K Street a few hundred feet from the Barclay, Sigal questions the dissidents' statements about the area's residential nature.

"Certainly the K Street corridor is not a residential district by any stretch of the imagination," she said.

New owner Locke also expresses bewilderment at how his building could hurt the community.

"I have tried to think of ways the Barclay House would hurt the neighborhood," said Locke, the 34-year-old businessman who, with two partners, took on the Barclay as a premiere investment. "It makes that much more property available to more people," he added.

Neighborhood committee head Nowick blames the zoning commission for having "weak and vague" definitions for hotel and apartment houses.

A hotel, under Zoning Commission definitions hammered out in 1979 after much discussion, is distinguished from an apartment essentially by having rental rooms available on a day-to-day basis. Since the Barclay plan includes titled ownership of the intervals, it is not considered a hotel.

Angry Foggy Bottom residents attended a Sept. 1 meeting with Sigal and Locke, and "fireworks broke out," Nowick said. But Sigal and Locke show no signs of backing down, and Nowick said he wasn't sure what steps neighborhood dissidents would take next.

He and his neighbors are alert for similar projects that might bring in more "hybrid hotels" to residential areas, Nowick said, adding that if other developers try to do the same thing, they might take the issue to the Zoning Commission.

Locke and local hotel consultants agree there has been considerable interest in Locke's project, but they say they do not know of plans for another interval-ownership condominium.

The Barclay House conflict is one of several skirmishes in a hotel-residential-area battle that has intensified in the past several years as demand has increased for commercial and residential space near the downtown area.

Last fall, for example, some of the same Foggy Bottom residents who protested the Barclay House declared war on the tour buses using the narrow street in front of the River Inn at 1660 25th St. NW. The River Inn is an apartment house that was converted to a hotel in 1978.

In the summer of 1980, Woodley Park residents bombarded the management of the new Sheraton-Washington Hotel with complaints about traffic congestion, extracting from the managers a promise to create about 900 new off-street parking spaces.

Widespread opposition from Adams Morgan, Dupont Circle and other areas focused on the expansion of the Washington Hilton Hotel in the spring of 1980 and was partially responsible for an April decision by the D.C. Zoning Commission to prohibit the expansion of hotels in residential areas and to limit hotel construction and conversions to "special-purpose" zones and to mixed-use and commercially zoned areas.

A month later, the D.C. City Council banned the conversion of apartment buildings into apartment hotels; the then-temporary ban now is law under the rent control section of the Rental Housing Act of 1980.

City officials say they now are investigating tenant complaints that developers of buildings at 800 Fourth St. SW and at 925 25th St. NW violated the apartment conversion ban."It's been pretty well demonstated by the City Council and the Zoning Administrator that there is not going to be any more expansion of existing or creations of new hotels in residential areas," said Howard Price, executive secretary to the District's zoning administrator.

Not that the pressure for new transient lodging is expected to decrease. District tourism officials say there has been a 5 to 10 percent yearly increase in visitors to the District over the past several years, and hotel industry officials say the completion of the huge convention center near Mt. Vernon Square could create demand for 6,000 to 8,000 new rooms by 1985. Presently, the metropolitan area has about 36,000 hotel and motel rooms, and several hotel developments are under way.