The designers of the Smithsonian National Museum were determined to provide a safe, healthy and aesthetically pleasing environment for its collections. First and foremost, that involved fireproofing not only the building’s exterior but also the masonry structure within it. Timber-framed buildings had proven to be a major fire hazard; the AIB, like many other 19th century buildings, was built using wrought iron structural members instead, to minimize that risk. The AIB’s original interior structure incorporated plaster-finished arches supported on tall piers, providing huge openings for maximum transparency, visibility, light and air throughout the building. The piers began to be filled in within the halls, courts, and ranges fairly soon thereafter, however, in an effort to further minimize the potential for fire spreading between exhibit halls.
The Advantages of Hollow Masonry
Architect Adolf Cluss was particularly concerned with the effective and economical heating and ventilation of the museum. He designed the plaster-finished walls to contain unreinforced masonry cavities. Hollow masonry construction helped to relieve moisture and to provide adequate space for insulation.
The interior of all the walls in the public spaces had a sand finish on the plaster with a texture (and, in some areas, black paint lining) to simulate a stone surface.