text: 1928 By March 1928, newspapers had reported that the Commerce and Internal Revenue buildings would be constructed first, followed by the Archives, then Justice, and then a newly added Post Office building. Plans continued for the demolition of the District Building and Southern Railway headquarters (although the latter would be the last to be razed, as it would be used as temporary office space for displaced federal workers). Although the Commerce building plans (a  building with  of office space, the largest office building in the world) had stabilized by March 1928, some designers suggested that both 15th and 14th Streets NW be submerged in tunnels beneath the structure. About the same time, the Internal Revenue building's square footage was reduced by almost a quarter to 500,000 square feet (46,500 square metres). In July, Congress appropriated $210,000 for design work for the Independent Offices, Interstate Commerce, Justice, and Labor buildings, and Secretary Mellon altered the work schedule yet again to focus on these structures. The Board of Architectural Consultants met to consider ways in which the construction program might be sped up, and devised plans to have four approved buildings (Commerce, Internal Revenue, Justice and Labor) completed by 1932. By October 1928, the Board of Architectural Consultants had agreed with prior decisions that no office building should be constructed on the National Mall, and that this space should be reserved for museums.