Portuguese government plans to renovate and expand its embassy and chancery complex on Kalorama Road NW won the unanimous approval of the city Board of Zoning Adjustment this week.

A second floor will be added to a west portion of the building, adding more than 1,800 square feet to the building which the Portuguese have owned since 1945. Most of the space--slightly more than 1,000 square feet--will be used for chancery--or office--functions, and the remainder will be an addition to the ambassador's residence.

Plans for the complex, surrounded by the diplomatic missions of France, Ethiopia, Algeria and China in the exclusive Kalorama neighborhood, were approved by the federal Commission of Fine Arts. Community comment was limited to a request from one couple, who live across the street, that adequate parking be provided on the embassy grounds.

It was the second application to be considered under emergency zoning regulations passed in April. The board last week granted a Japanese government request for permission to begin a two-phase building program on its Massachusetts Avenue chancery property.

The emergency rules were approved to allow other governments to go ahead with building or renovation plans while the District completes revisions of its zoning regulations to comply with the Foreign Missions Act. The act, which was passed by Congress last year and became law last Oct. 1, requires foreign governments to get State Department permission to buy, sell, rent or expand property in the United States.