Allen Hall comprises six stories (a ground floor and 1st–5th floors) using granite for the lower two stories and buff brick for the next three stories; the 5th floor is windowless and concealed by the roof.
Due to the building's age and landmark status, and despite internal renovations, all floors, with the exception of the 1st (following the most recent renovation) and 3rd (due to the flying tunnel connection to NPL), have only one bathroom; the bathrooms alternate male-female, with the fifth floor's being coed.
This is due to a space-saving decision by the original designers that women's bathrooms were unnecessary in a science building.
The building is linked on the first three floors to neighboring Old Engineering Hall, and on the 1st and 3rd to the Van de Graaff Building housing the Nuclear Physics Laboratory located at the rear.

The facade at the entrance of this building has a plaque to honor Madame Curie, commemorating the 100th anniversary in 1967 of her birth, the conferring of an honorary degree in 1921, her visit to the plants of the Standard Chemical Company, its role as a major radium producer and in the making of the gram of radium presented to Marie Curie by President Warren G. Harding, and the role of Glenn Donald Kammer, a University of Pittsburgh graduate who supervised its production.
The plaque was unveiled on September 20, 1969, by the Archbishop of Kraków, Poland, Cardinal Wojtyła, who in 1978 became Pope John Paul II.

Renovations, upgrades, and improvements for Allen Hall, Old Engineering Hall, Van de Graaff Building and Thaw Hall, were carried out from 2011–2013, with the creation and renovation of 13 Department of Astronomy and Physics laboratories located in Allen Hall, Old Engineering Hall, and the Van de Graaff Building.
To allow for major internal reconstruction, Allen hall was temporarily vacated for the 2012–2013 academic year, with residents relocated to Thaw, Old Engineering, and Thackeray Halls.
The renovations were completed on schedule and Allen was reoccupied at the beginning of the 2013–2014 academic year.
The most unusual result of the renovations was the installation of a double rail over the original railing in the main staircase, due to it being below regulation height.
Allen Hall comprises six stories (a ground floor and 1st–5th floors) using granite for the lower two stories and buff brick for the next three stories; the 5th floor is windowless and concealed by the roof. Due to the building's age and landmark status, and despite internal renovations, all floors, with the exception of the 1st (following the most recent renovation) and 3rd (due to the flying tunnel connection to NPL), have only one bathroom; the bathrooms alternate male-female, with the fifth floor's being coed. This is due to a space-saving decision by the original designers that women's bathrooms were unnecessary in a science building. The building is linked on the first three floors to neighboring Old Engineering Hall, and on the 1st and 3rd to the Van de Graaff Building housing the Nuclear Physics Laboratory located at the rear.
The facade at the entrance of this building has a plaque to honor Madame Curie, commemorating the 100th anniversary in 1967 of her birth, the conferring of an honorary degree in 1921, her visit to the plants of the Standard Chemical Company, its role as a major radium producer and in the making of the gram of radium presented to Marie Curie by President Warren G. Harding, and the role of Glenn Donald Kammer, a University of Pittsburgh graduate who supervised its production. The plaque was unveiled on September 20, 1969, by the Archbishop of Kraków, Poland, Cardinal Wojtyła, who in 1978 became Pope John Paul II.
Renovations, upgrades, and improvements for Allen Hall, Old Engineering Hall, Van de Graaff Building and Thaw Hall, were carried out from 2011–2013, with the creation and renovation of 13 Department of Astronomy and Physics laboratories located in Allen Hall, Old Engineering Hall, and the Van de Graaff Building. To allow for major internal reconstruction, Allen hall was temporarily vacated for the 2012–2013 academic year, with residents relocated to Thaw, Old Engineering, and Thackeray Halls. The renovations were completed on schedule and Allen was reoccupied at the beginning of the 2013–2014 academic year. The most unusual result of the renovations was the installation of a double rail over the original railing in the main staircase, due to it being below regulation height.
Allen Hall (University of Pittsburgh)