Logistics & Materials Handling Blog

What is Selective Racking - Warehouse Racking Guide: Part 2

by Paul Hinz
Filed under: Warehousing

What is Selective Racking? Part 2 of this guide focuses on Selective Pallet Racking. We will look at the key features of Selective racking & analyse the key advantages and disadvantages.

Selective Pallet Racking is the most common type of warehouse racking; it has the lowest pallet storage capacity; but is also the lowest cost per square metre of racking. However, in terms of high volume storage greater than 3000 pallets it’s often the most expensive solution.

Narrow aisle yellow

Layout

Selective Racking is only one pallet deep; with a maximum of two racks being able to be placed back to back. (See Selective Packaging Basic Layout Diagram)

Pallet Access (FIFO)

Selective Pallet Racking provides direct access to every pallet in storage. For low turnover volume & high differentiation product lines this type of racking is a must.

This means it’s a First In First Out (FIFO) racking type (meaning the stock added in first is also removed first, compared to Last In First Out (LIFO) systems. (Which means that pallets are inaccessible until all the newer stock is removed (see Push Back Racking as an example of LIFO)?

FIFO ensures that perishable or short shelf life SKU’s are able to be turned over effectively.

Aisle Width

When it comes to Selective Pallet Racking; aisle width is a major factor for storage capacity. Storage capacity can be as low as 35% to as high as 75% depending on the type of pallet handling equipment you choose (take a look at this basic layout guide to get an idea. (Refer Selective Racking Forklift application guide lines)

Remember that narrow width aisles don’t always equal lower storage cost. Narrow width aisles lower the forklift operator’s margin of error. This can lead to slower handling times which can outweigh the benefits associated with greater storage. Ensure you compare these costs before making a decision.

Advantages

  • Access large range of Stock Keeping Units (SKU’s)
  • First In First Out (FIFO) inventory management.
  • Cheapest type of racking (Per square metre)
  • Multiple access (more than one truck in same aisle)
  • No special truck requirements
  • Lower Forklift or Pallet Handling costs; as standard forklifts are cheaper than specialised equipment.
  • Floor level is not critical (front loaded)

Disadvantages

  • Requires large amount of warehouse space to store high volume of stock.
  • High storage cost when volumes are medium and above
  • Increased loading and unloading times of limited product or stock lines; as the same stock would need to be placed on different individual rack heights/widths.
  • Poorly suited for high volume applications; with limited SKU’s
  • Limited storage height (12m)

Forklift Racking application guide:

Counter Balance forklift (wide aisles for low Volumes)

  • Aisle widths – 3.8 to 5.5m
  • Storage Area – 35%
  • Lift height – up to 8m

Reach Truck (narrow aisles for medium to high volumes)

  • Aisle widths – 2.8 to 3.2m
  • Storage Area – 45%
  • Lift height – up to 10.5m

Articulated Forklifts (very narrow aisle for high volumes)

  • Aisle Widths – 1.8-2.2m
  • Storage Area = 60%
  • Lift height – up to 12m