Traditional wooden pigeon hole frames require mail to be horizontally sorted to street or street segment followed by a finger sort on the desktop to put that mail into sequence of the delivery round.  This requires high skill levels and detailed knowledge of the round sequence order.

To process mail into round sequence on a vertical sorting frame is an one-step process.  Mail is sorted to a labelled address slot in a single action.  Both small and large letters can be sorted to the frame and all mail is then available to pull down in address sequence.  Where mail volumes exceed 300 items, or delivery points are greater than 300, the time taken to sequence mail on a vertical sort frame is less than on a horizontal sort.  The benefits increase as either volumes or delivery points increase beyond those levels.  Significant productivity and quality gains will be achieved through the introduction of vertical sorting and improved processes.  Experience shows a real productivity increase of 15% to 80%.

Even in circumstances where mechanised sequence sorting takes place, vertical sorting frames provide benefits for:

• Rapid sortation of mail that for some reason has not been mechanically sequenced
• Merging of sequenced and unsequenced mail
• Merging of different mail formats, such as small and large letters, which may have been individually sequenced.