After a two-year battle, preservationists this week dealt a decisive blow to a landlord seeking to build a parking garage at his historic Brooklyn Heights development.

The Landmarks Preservation Commission indicated Tuesday it would turn down the proposal, effectively tabling the application. The landlord, the Pinnacle Group, can return with a redesigned proposal for an underground parking garage.

The company had planned to construct a two-level parking garage in the courtyard of the Riverside Apartments, at the corner of Joralemon Street and Columbia Place. The Riverside, built by philanthropist Alfred White in 1890, also has a historic courtyard, and the Pinnacle Group had planned to replace it with a landscaped garden designed by a former Landmarks Preservation commissioner, the landscape architect Lee Weintraub.

An attorney for the Pinnacle Group, Kenneth Fisher, said yesterday that the head of the company, Joel Wiener, would “look at the technical feasibility and economics” of an underground garage or withdraw the application.

“It’s not entirely clear what course we’re going to take,” Mr. Fisher, a partner at the law firm WolfBlock, said.

The president of the Brooklyn Heights Association, Tom Vandenbout, said opponents of the plan are “cautiously celebrating” in the wake of the decision, which came after a two-hour public hearing.

“Everybody is at least at the moment breathing a sigh of relief,” he said. “That doesn’t mean the owner won’t come back with another idea.”

In 2006, Mr. Wiener proposed building a 134-car, two-level parking garage in the complex’s courtyard, which was partially removed in 1964 to make way for the Brooklyn-Queens Expressway. The courtyard was damaged further in the early 1990s, when a previous owner paved a portion of the remaining space.

The Pinnacle plan met with strong opposition from the tenants of the 157-unit complex, the Brooklyn Heights Association, and Community Board 2. The Landmarks Preservation Commission also raised objections, driving Mr. Wiener to withdraw his initial application.

In March, Mr. Wiener submitted a new design, this time with plans calling for a garden to be planted above the garage, approximately 14 feet above grade.

The developer argued that the garage would meet a critical need for parking in the area. Brooklyn Heights is slated to lose some 400 parking slots when condominiums replace a garage on Love Lane. Construction on the new development is currently under way.

Mr. Fisher added that the garden would improve the look of the courtyard, particularly as the commission determined that the space had little historic value in the 1990s, when it permitted the paving.

A number of residents, scholars, and community members took strong exception with the idea, saying the plans disrupted the historic character of the building.

“The Riverside Houses complex is one of the most important buildings in the history of 19th-century housing in New York and Brooklyn,” a member of the Municipal Art Society’s preservation committee, Benika Morokuma, said. “By constructing a garage in the courtyard, the current owners will be undermining the innovations that White intended for this groundbreaking housing complex.”

Mr. Fisher said parking spots in the garage would have been offered first to complex residents at a discount, then to the general public.

An architectural historian, Lisa Ackerman, said during the meeting that White was famous for his efforts to improve the lives of New York’s working poor with housing that maximized light and ventilation. The large courtyard at the Riverside Apartments was intended for the “health benefit and enjoyment of the tenants,” she said, and it set a precedent for similar designs at future buildings, including Stuyvesant Town and Peter Cooper Village.

“The construction of a garage, even if the roof is landscaped, is a complete negation of the principles by which Riverside was built,” Ms. Ackerman said. Residents also cited concerns about safety, noise, and congestion.

Ms. Morokuma added that the project could damage archaeological resources on the site, which was used as a brewery in the 18th century and lies on the site of the natural high water line.

The majority of commissioners said they would not support the proposal. Because the BQE had already damaged part of the courtyard, “it behooves us to preserve what is left,” Commissioner Libby Ryan said. “I could consider a proposal that will put a garage entirely underground.”

Some commissioners praised Mr. Weintraub’s design but said it was inappropriate for the space. The architect did not return calls for comment.

“We were encouraged that a couple of commissioners recognized that the courtyard has very little of its original historic fabric to it,” Mr. Fisher said. “We were disappointed that they did not see the value of creating a terrific garden, elevated one level up by the parking garage.”