Consequently, the construction of the temporary building of the Congress Hall, which had two stories, was started and the main building was completed in 1890 when the First congress of the Imperial Diet was opened (the reference of History of the Diet Building.)
結局、議事堂は木造2階建の仮建築で実施され、第1回帝国議会開会の1890年に竣工した（国会議事堂歴史参照）。