The D.C. Zoning Commission voted final approval yesterday of a regulation to curtail high-rise commercial development on a historic three-block section of Connecticut Avenue above Dupont Circle.

The commission also voted to permit George Washington University to erect an 11-story, glass-fronted commercial office building behind Red Lion Row, a group of 19th century town houses that face two triangular parks in the 2000 blocks of I Street and Pennsylvania Avenue NW.

In both instances, the commission -- a municipal body -- rejected formal contentions by the federal government's National Capital Planning Commission that both actions would have harmful effects on federal interests in the city. Since limited home rule began in 1975, NCPC's once-decisive role in city planning and zoning has been reduced largely to one of giving advice.

Before yesterday's vote, George M. White, the architect of the U.S. Capitol, who by law serves on the zoning commission, criticized NCPC for its recommendations. Since home rule, he declared, NCPC "has been taking a view of us against them, the federal against the local . . . an unfortunate result."

With its Dupont Circle vote, the zoning commission reduced the permitted height of buildings on both sides of Connecticut Avenue from the current 90 feet to 70 feet between the circle and Florida Avenue. That would allow future buildings as tall as six stories. Civic groups wanted a 50-foot limit to maintain what their spokesmen described as a human-scale neighborhood.

NCPC said the federal government has an interest in maintaining the historic buldings currently along the avenue, which are mainly three to five stories high.

In the George Washington University case, NCPC took a position similar to neighborhood groups is asserting that the new commercial building would visually overwhelm Red Lion Row and the two triangular parks, which are part of the 1791 L'Enfant plan for the city.

The zoning commission's majority rejected that view, and in a formal order said the project should proceed because, among other things, it will produce $1 million in annual real estate tax revenues for the city.

The project still is subject to review by the city's Joint Committee on Landmarks, which must approve any alterations to Red Lion Row.

In both of yesterday's decisions, only John Parsons, associate regional director of the National Park Service, cast votes in opposition.

In another action, the commission scheduled a hearing for 1:30 p.m. June 15 on a proposal to erect 70 dwelling units on the 13.7-acre Phillips estate at Foxhall Road and W Street NW.The proposal has stirred a neighborhood controversy, mostly over traffic arrangements.