The Montgomery County Planning Board last week approved one section of new plans for Timberlawn, a major subdivision south of Rockville that the developer began as high-priced detached houses, and then decided to convert to high-density attached dwellings.

The board approved the preliminary plans for 16 acres of the subdivision, but deferred a decision on a 90.6-acre tract because members questioned the developer's plans to widen a road.

The developer, U.S. Home Corp., had originally intended to build approximately 300 single-family detached homes that would sell for $200,000 and up on the former Timberlawn estate of Sargent Shriver.

But after completing about 30 of them two years ago, U.S. Home announced that the market had changed and applied for rezoning to accommodate denser development. The county agreed to the rezoning last year.

At first, residents who had purchased homes opposed plans to build 902 town houses in the remainder of their neighborhood, according to Jon K. Ericson, division president of U.S. Home.

But, Ericson said, the neighbors agreed to the development after the company made a number of promises, included creation of a buffer zone between the single-family homes and the town houses.

"We came to an agreement over a year ago," he said. "It has been quiet on that front."

However, the nearby Old Georgetowne Citizens Association and a handful of other neighborhood groups contested the Timberlawn rezoning, said Charles R. Loehr, subdivision coordinator for the county. This summer, the county circuit court backed the rezoning; no appeals have been filed, he said.

Officials of the association could not be reached for comment.

Loehr said the preliminary plans for the 902 town houses show that a road that runs through the established single-family section of Timberlawn would have to be widened from 26 feet to 36 feet to accommodate traffic exiting onto Edson Road.

Timberlawn, off Edson Road and Tuckerman Lane, is approximately a half-mile from the Grosvenor Metro station.

"There was some question as to whether they could get an easement or a right of way," said Loehr, who said the home owners along the road would be notified that it may be widened.

Ericson said U.S. Home is also contacting the home owners and hopes to resolve the road problem as quickly as possible.

"Obviously, we wish we could start construction yesterday," he said. "We've been at this for years now."