What Is Very Narrow Aisle Pallet Racking (VNA)?

In its simplest description, very narrow aisle (VNA) pallet racking is a high-density variation of a traditional pallet racking system, but it increases the capacity of the warehouse by up to 40%, without expanding floor area or vertical space.

It is usually a type of adjustable pallet racking system which is compacted, by narrowing the aisles to a minimum width of 1.5 metres. However, this type of racking system requires specialised handling equipment and careful route planning.

For expert advice and assistance on how Warehouse Management Software (WMS) like ProWMS and ProSKU SaaS integrates with very narrow aisle pallet racking systems, contact Principal Logistics Technologies for professional advice. Give us a call on 0161 888 2580 or email info@principalsystems.com.

To understand VNA pallet racking better, let’s unpack the concepts involved.

 

What is industrial racking in a warehouse?

A warehouse without racking or shelving is a contradiction, and such a beast does not exist. Simplified, industrial racking is the construction and layout of shelving structures, usually made of metal or a combination of materials, to support and store inventory as part of the supply chain.

The correct choice of racking or shelving, and thoroughly planning its layout, will streamline operations. The opposite is true if the type and configuration of the racking or shelving system, its aisle widths, docking locations, and shipping areas, do not maximise the storage space and movement of inventory.

The type and layout of racking impacts directly on your warehouse efficiency, budget, and profitability. It is therefore imperative to select the right type, style, and design and thoroughly plan the picking and movement of goods in the warehouse.

 

What is the difference between industrial racking and shelving in a warehouse?

Advanced, versatile, and adaptable structures, usually made of strong metals, have been researched and designed to strategically store goods most effectively and efficiently in a warehouse, according to the SKUs and characteristics of the inventory, including size and weight; volumes or frequency of movement; and perishability or lifespan before obsolescence.

In warehouse management, industrial racking is usually divided into two main groups, pallet racking; and shelving solutions.

 

Industrial racking

Industrial racking is typically used for storing heavy items and for bulk storage needs, using special equipment to stack the pallets in a vertical space.

Pallet storage systems

Also called racks or skids, pallets are made from metal, wood, or plastic, in a range of sizes, widths, and lengths, and they are often combined with various types of racking and shelving systems.

Racking systems

Racking systems are more expensive than shelving but can hold much greater weight.

Racking generally takes up more space than shelving but it is easier to direct and immediate access to large and bulk items.

The main types of racking systems, each with subdivisions, are:

Adjustable pallet racking

It has a standard aisle width between 2.5m and 4m, that runs parallel to the racking, to directly access goods, using forklifts. The racking is adjusted to the width of the pallets used.

Very narrow aisle-racking

A type of compact racking, VNA racking is a high-density storage variation on the standard adjustable racking system that fully optimises warehouse floor space and height by reducing the aisle width to a minimum of 1.5m.

The two main types of VNA racking are drive-in pallet racking with an entrance at one end and an exit at the opposite end; and drive-through pallet racking which can be accessed from both ends of the aisle.

Narrow forklifts or trucks are required to access the narrow aisles below.

Double-deep racking systems

Used to store pallets at two depths, reducing the number of aisles.

Forklifts with telescopic or pantograph-type mechanisms are used to access pallets at the back of the racking system.

Live pallet racking

This is another type of compact racking automated storage system that uses gravity and pushing, on roller beds, to move pallets to their correct positions on the racking system,

Mobile pallet racking systems

Racking bays are mounted on mobile bases on rails or tracks, usually fitted with electric motors remotely operated to move pallet racking bays around for access to goods.

Cantilever racking systems

These are used to store long items such as pipes or timber at the top of the racking system.

 

Shelving/Picking Solutions

Shelving is typically used for lighter items, stacked by hand in boxes, bins, or individually.

  • Shelving is cheaper than racking but is severely limited in the weight and size it can hold.
  • Shelving takes up less and less floor space now, but items are often harder to reach at the back, particularly at greater heights.

Four main types of shelving used include:

  • Steel Shelving, known for its durability and strength
  • Rivet Shelving is a simple storage solution, assembled without bolts and nuts, used to store products in cases.
  • Wire Shelving is typically a freestanding structure consisting of four uprights with a varying number of wire mesh shelves attached to them.
  • Bulk Rack Shelving is considered a compromise between heavy

 

What special equipment is required for a very narrow aisle pallet racking system?

For very very narrow aisle racking system systems, special equipment, such as VNA trucks or forklifts, with rotating forks, telescopic forks, or pantographic mechanisms is required.

Floor and guidance systems and route plans for the operation of these vehicles are essential to avoid traffic jams, accidents, and inefficient loading and stacking operations.

 

What are the benefits of a very narrow aisle pallet racking system?

  • Radically increased storage capacity, and storage density, especially for bulk storage.
  • Space utilisation is optimised, leading to cost savings.
  • It improves operational efficiency and helps with faster order fulfilment.
  • Versatility and adaptability because height and depth can be varied greatly.
  • Enhanced safety and security because support systems allow drivers to concentrate on loading and unloading, rather than steering their vehicles.
  • It gives easy and direct access to all pallet levels.
  • It requires minimal maintenance and reduces damage costs if utilised correctly.
  • It is ideal for high-roofed warehouses, to exploit vertical storage and optimise floor space.
  • VNA combines the benefits of standard adjustable racking systems and other forms of compact racking because space is better utilised while retaining direct access to goods.
  • It is a robust system that can easily be adapted as circumstances change.
  • Although the VNA racking system is used primarily for full pallet storage and retrieval, it is also eminently suitable for item picking.

 

What are the disadvantages of very narrow aisle racking?

  • Potential for increased damage to pallets and racks if special equipment and safety systems are not used properly.
  • Safety considerations if proper systems are not in place and guidelines are not strictly adhered to.
  • It requires special equipment to manoeuvre in the narrow space.
  • It requires special guidance systems at floor level to ensure precise positioning of forklifts.
  • The warehouse floor must be perfectly flat and level because VNA racking is typically higher than standard racking, so any tilt at lower levels is accentuated at the top.

 

How is a very narrow aisle pallet racking system managed as part of WMS?

To achieve handling efficiency levels equal to, or exceeding, those for wide aisle, traditional racking systems, ProWMS and ProSKU warehouse management software seamlessly automates virtually all processes, including the following requirements for VNA pallet racking systems:

Compliance with pallet rack regulations:

Regulations governing racking and shelving storage systems, operational procedures, and health and safety compliance, can be very complex and even vary from one region to another.

ProWMS and ProSKU SaaS modules can be added to guide you through all the compliance issues and help you design and maintain policies and operational systems, including regular inspection and maintenance plans.

Automation of Material Handling Equipment (MHA)

Material handling equipment used for moving, storing, controlling, and protecting inventory throughout the warehousing process, can be automated in different ways. This can be done by means of installed rails or electrical contacts, or automated instructions to the receiver and driver of the forklift or truck.

 

Pallet handling

ProWMS and ProSKU SaaS include optional modules which provides VNA racking configuration for “pick-and-drop” pallet/product handling. It provides an automated, paperless, instruction on our mobile application for each separate stage of the putaway or pick to store or retrieve a specific pallet/product.

As an example, the receiver scans a pallet to identify it and receives instructions to deliver it to a P&D station. The aisle truck or forklift driver then receives an automated instruction to pick up and place the pallet in the allocated rack space. The process is reversed for an outgoing pallet/product..

 

Get in Touch

Contact us today for more details on our WMS VNA functionality and how it can help optimise your warehouse operations. You can call us on 0161 888 2580, or email info@principalsystems.com