The developer of Timberlawn, a Montgomery County subdivision originally scheduled to contain luxury detached houses, this week ran into more opposition to its plan to switch to high-density attached units.

The developer, U.S. Home, has spent most of the past year wrangling with about 30 homeowners who bought early into what was expected to be an area of 300 homes situated on third-of-an-acre lots and selling for $200,000 and up.

U.S. Home finally worked out a compromise with this group under which, in exchange for changes in the developer's site plan, the group would drop opposition to construction of more than 900 attached houses on the remaining land.

U.S. Home, however, still must obtain a zoning change from the county, and this week, at hearings on its request, residents of neighboring communities attacked the proposal.

Representatives of residential associations surrounding Timberlawn--a 95-acre tract north of Tuckerman Lane and east of Rockville Pike--and an adjoining 16-acre tract owned by Berger-Berman Inc., said the proposed high-density development will ruin the character of their communities, which grew up around what was once the rolling farmland estate of Sargent Shriver.

Old Georgetowne Citizens Association, Edson Lane Citizens Association, Luxmanor Citizens Association and the North Bethesda Congress (an umbrella group of civic associations) all oppose the zoning change.

Beatrice Chester and Alan Malasky of the Old Georgetown Village Citizens Association argued before hearing examiner Phillip J. Tierney that the increase in residents will create "extreme pressure" to make Edson Lane--north of the subdivision--a through road connecting Old Georgetown Road and Rockville Pike. Tuckerman Lane, which borders on the south, also is closed off between the two major roads, but is scheduled to be opened around the time the new Metro subway station does.

According to Alan Davies, a resident of Luxmanor who is representing his group, the increased traffic would create "a China Wall" separating the neighborhoods and would bring a flood of commuter traffic.

Witnesses brought by the land companies in hearings this week included land planners and architects, a noise expert and members of the County Planning Board's staff, Tierney said. They presented studies and statistics contending that the demand presented by the surge in population wouldn't exceed established limits on traffic congestion, water and sewer service and area schools.

The County Planning Board also has endorsed the rezoning.

Tierney said the County Council will decide the case later this spring, after he submits his recommendation some time around the beginning of April.

Timberlawn currently is zoned for large homes on one-third-acre lots, but lawyers for U.S. Home earlier this month won the support of County Planning Board Chairman Norman L. Christeller, who approved their request for denser zoning.

In fact, the land, adjacent to Rockville Pike and close to the White Flint Metro subway station, once was listed in long-range county plans for town-house-style subdivisions. But U.S. Home won a change allowing it to build the larger homes. Then, after 33 families bought large homes in what was promised to be a wooded enclave of big yards and quiet cul de sacs, U.S. Home changed plans.

Company officials said economic conditions forced the shift.