Precast/Prestressed Girder groups commonly used data together in the form of Libraries. Libraries are used to store data that does not change often and is to be used repeatedly across projects. The four library types available in Precast/Prestressed Girder are Beam Sections, Prestressing Tendons, Rebar, and Live Loads, all of which store information as suggested by their titles.

The individual libraries are stored as files, each file containing different items. For example, a beam section library file named My I Girders and Box Beams.cs1 may contain 5 different I-girders and 20 different box beam sections.

Precast/Prestressed Girder is released with a set of default libraries for beam sections, prestressing tendons, rebars, and live loads. Most users may find it convenient to work with a single library file, modifying, adding, and deleting items in these files rather than creating and setting up different /multiple library files.