Old and New!
https://en.wikipedia.org/wiki/Cannon_House_Office_Building
How a Building Changed the House: Cannon House Office Building
http://history.house.gov/Exhibitions-and-Publications/Cannon-Building/Cannon-Building/
The Original House Office Building Opened for Occupation
http://history.house.gov/Historical-Highlights/1901-1950/The-original-House-Office-Building-opened-for-occupation/
The Naming of the House Office Buildings On this date, President John F. Kennedy signed H.J. Res. 711 into law (Public Law 87-453), naming the House Office Buildings to honor three famous Speakers of the House: Joseph Cannon of Illinois, Nicholas Longworth of Ohio, and Sam Rayburn of Texas. Prior to the designation, the Cannon Building (opened in 1908) was known as the Old House Office Building while the Longworth Building (opened in 1933) was known as the New House Office Building. A former House Member, President Kennedy laid the cornerstone for the Rayburn House Office Building on May 24. The Rayburn Building opened for occupation on February 23, 1965. Before the construction of the House Office Buildings, Members worked at their desks on the House Floor or in their boarding houses
http://history.house.gov/Historical-Highlights/1951-2000/The-naming-of-the-House-Office-Buildings/