Precast structures should be designed and detailed so that the complete structure will be safe, functional, aesthetically appealing, and economical. No structure is exactly level, plumb, straight, and true, so all construction and materials should be specified with tolerances limiting deviation from design values. These tolerances require monitoring to construct the structure as designed.
Tolerances are typically divided into three primary categories:
Product tolerances
Erection tolerances
Interfacing tolerances
Overview of tolerances related to the precast concrete structures industry.
(Adobe PDF File)