Portland’s Planning Board has approved a plan to construct two new office building next to the Elks Lodge on outer Congress Street. The project includes a renovation of the Elks Lodge as well as the construction of a 25,300-square-foot medical office building and a 15,000-square-foot general office building on the 7-acre property. The Planning Board voted 5-0 Tuesday to approve the plans. The office development was made possible by a zone change approved by the City Council in January.