The original library building was built in 1912-1913. Although it has the appearance of a Carnegie Library, it is not. When the city applied to the Carnegie Foundation for assistance in funding, the amount which the Foundation was willing to provide was insufficient to build the library. Moose Jaw turned down the amount offered and funded the building through a debenture. The building, its furnishings and collection cost $110,000. The debenture was eventually paid off in the early 1930′s by which time the Library was already in need of expansion.
The original building was designed by Charles Curtis McAlpine and George D. Reid. Among its many unique features were the marble rotunda, a stained glass dome and a glass floor in the stack area. The marble in the rotunda was quarried in Quebec.
In 1992 an expansion at the rear of the original building was completed. The expansion connected the existing library and Art Museum buildings and provided much needed additional space for both operations. For the library, the expansion allowed one of the original reading rooms and both of the meeting rooms to be returned to their intended use. The collection and much of the study area is housed in the expansion. De lint & Taylor were the architects for the expansion. In order to build the expansion the rear wing which housed the glass floor and part of the stack area had to be removed. A portion of the glass floor was incorporated into the expansion. Although controversial at the time, the final product of the expansion to the two buildings is a pleasing blend of the old and the new which is much more practical and efficient to use.