Shelving is a very basic storage method which affords the user significant flexibility in the type and quantity of goods stored and at a relatively low capital investment. Consequently, shelving is by far the most popular samll parts storage technique used in warehouse. Most of these applications are well justified. The warehouse planner, however, must not approach the specification of a shelving system with any less care than that of an automated storage/retrieval system. An examination of the shortcomings of typical shelving installations reveals why.
Shelving is not an inherently space-efficient storage technique. Cubic space utilization within a typical shelving installation is often less than 50 percent. There are two primary reasons for this poor space utilization. First, shelving installations often make poor use of the vertical space available in a warehouse. Installation of 84-inch-high shelving in a facility with 20 feet of available clear stacking height is all too common. The result is significant unused, wasted space.
The second problem is that every individual shelf opening has the potential for poor utilization of space. It is not unusual to see a typical shelf opening that is 36 inches wide, 19 inches deep and 12 inches high being occupied by a 6-inch-cubed box. Many shelves are occupied more by air than product.
These space utilization problem directly result in increased warehouse costs related to the amount of shelving required and the amount of warehouse space required to house the shelving. Additionally, they directly lead to emplyee productivity losses in that the warehouse personnel must travel greater distances within the shelving system to access shelf locations. The point is that proper shelving specificaion can minimize such problems. Shelving is a simple storage system, but the warehouse planner must not be simpleminded in its application.
