On Wednesday night, Lower Merion Township commissioners unanimously adopted a new zoning map for the town of 4,380 residents that they called a blueprint for reigniting the business district while protecting adjacent neighborhoods.

"It is a very exciting opportunity," said Commissioner V. Scott Zelov, who chaired an ad hoc committee of civic and business leaders who worked for more than a year drafting the village zoning strategy.

The four zoning classifications will not take effect until the adoption of an ordinance that spells out building standards for each, including allowable uses, heights and density. The commissioners expect to vote on that June 18.

Two years ago, a consultant hired by Lower Merion identified Bryn Mawr's 1920s-era zoning regulations as an obstacle to the makeover of the low-rise village.

The township envisions boutiques, cafes, offices and townhouses sharing the blocks along Lancaster Avenue, and, in the town square, a hotel as tall as five stories on what is now a 1.9-acre parking lot just steps from the R5 train station.

The prospect of an additional month's delay in replacing the outdated building rules did not seem to dash the enthusiasm of some audience members at Lower Merion's township building Wednesday.

"This will be extremely instrumental in having Bryn Mawr revitalized," economically and as a "cultural destination," Juliet Goodfriend, president of Bryn Mawr Film Institute, told the commissioners before the vote. The nonprofit community theater was part of the ad hoc committee.

Seated on the room's other side, a decidedly dour Elba Doorly offered her assessment in private: "I am very disappointed."

While Goodfriend eagerly awaits increased traffic to the institute's doorstep on Lancaster Avenue - Bryn Mawr's commercial spine - Doorly worries about what the zoning plan might attract to nearby Central Avenue, where she and her husband live.

Their two-story brick rowhouse, in Doorly's family nearly 30 years, is one of three still occupied on Central. Seven sit vacant, presumably to be demolished as 18 neighboring homes were in summer 2006.

Their owners sold their rowhouses and twins to Bryn Mawr Hospital's real estate division. The hospital wants to build a garage on Central, along with houses and possibly shops or other commercial enterprises.

The new map puts Central - once an everybody-knows-everybody, affordable neighborhood in one of the most affluent Pennsylvania communities - in a zoning category that allows for a variety of uses.

That will better ensure that the street returns to being a residential neighborhood, the commissioners told a skeptical Doorly. They rejected her request to approve an exclusively residential zoning classification for Central.

Zelov and others said parking and lot-size requirements for residentially zoned areas would preclude building the same number of homes on Central that were there long before township zoning was implemented.

To help protect Central from becoming lined with stores under the new village zoning, the commissioners said they were prepared to limit the off-site public parking spaces for any new development there to 10. With such a restriction, Zelov said, "stand-alone retail is extremely unlikely, if not impossible," on that street.

Doorly wasn't buying it.

"Allowing the rebuilding of a residential neighborhood is not the same as ensuring it," she told commissioners.

Without zoning that prohibits anything but residences on Central, what could be built around her home "is very unpredictable," Doorly said. "And that is my agony."