Choosing the right storage systems is one of the biggest challenges of warehouse management. Many companies struggle to strike the right balance between modern automated systems, like vertical lift module (VLM) technology, and cheaper conventional alternatives, like traditional shelving. They often mistakenly feel that they need to pick either one or the other to handle their growing inventory.

In reality, there can be a place for both older and newer storage options in a successful warehouse. Both have their benefits and best use cases, and may improve important metrics, such as throughput and floor space utilization. Understanding these storage systems is vital for choosing the right ones for your warehouse, and the BoxLogix automation experts will detail the differences between them in this blog.

Key Takeaways

• VLMs maximize vertical space and improve picking efficiency by automatically delivering stored goods directly to workers.
• Traditional shelving offers a simpler, lower-cost storage option that can work well for bulky, irregular, slow-moving, or lower-SKU inventory.
• Many warehouses can benefit from a hybrid storage strategy, using VLMs for fast-moving, high-SKU inventory while keeping other products on traditional shelving.

What Is a Vertical Lift Module?

A VLM is a type of self-contained automated storage and retrieval system (ASRS). It features an enclosed elevator mechanism that can move up and down inside the unit to collect products from a series of trays, which are stored vertically, one on top of the other. Once a relevant tray has been retrieved, the elevator delivers it to a human worker via an ergonomic access opening at the base of the VLM.

A VLM is an example of goods-to-person automation, in which products are delivered directly to workers. It can integrate with inventory software or a warehouse management system (WMS) to streamline stock management and order fulfilment processes, and it can help with maximizing storage density by stocking products vertically while taking up just a small amount of floor space.

Common uses of a VLM include:

• Medical/industrial parts
• Tools
• Machine components
• High-SKU inventory

What Is Traditional Shelving?

Traditional or static shelving is a conventional type of warehouse storage made up of metal or wooden horizontal shelves suspended between vertical posts. They can vary in size and capacity, but all follow the same relatively simple design, which doesn’t involve any sort of automated technology or advanced mechanisms to find and retrieve goods.

Traditional shelving is used in person-to-goods warehouse systems, in which workers have to walk down aisles to find and collect items manually, sometimes with the aid of carts and ladders. Some of the advantages of systems like these include the fact that they’re much cheaper to set up. For instance, a traditional shelving rack costs far less than a vertical lift module.

Common traditional shelving uses include:

• Light to medium-weight goods
• Boxes
• Bulky or irregular inventory
• Low-SKU facilities

Vertical Lift Modules vs. Traditional Shelving: Key Differences

Aside from the obvious differences in appearance and usage, there are several additional ways in which traditional shelving and vertical lift modules differ. Some of the most important factors to compare include:

• Space utilization
• Picking efficiency and throughput
• Labor requirements
• Inventory accuracy and control
• Ergonomics and safety
• Cost and ROI

Space Utilization

Traditional shelving units require large amounts of floor space to store high quantities of goods. They can be positioned side-by-side to form vast aisles that can extend all the way across the warehouse floor.

On the other hand, a vertical lift module stores items vertically, making the most of the facility’s ceiling height to reduce storage footprint and free up space for other uses and operations.

Picking Efficiency and Throughput

Generally speaking, goods-to-person systems, like vertical lift modules, tend to result in more efficient operations. They can improve picking speed and picking accuracy, as well as minimize travel time for workers, which can also help with morale and reduce the risk of worker fatigue and injuries.

Person-to-goods systems, meanwhile, put much more physical burden on warehouse staff.

Labor Requirements

Using a vertical lift module can be less labor-intensive than navigating aisles of traditional static shelving systems. With a VLM, a worker can simply place themselves at the module’s hatch or access opening and wait for goods to be delivered right to them. This makes it easier for them to handle more goods and process more orders per day than if they had to travel around the warehouse.

Inventory Accuracy & Control

Automated systems such as VLMs also tend to result in higher levels of order accuracy and inventory control, reducing the possibility of picking errors. This is because VLMs work in conjunction with warehouse software to track the exact positions and movements of goods.

They also control access to the products stored within them, whereas shelves are more open and accessible, which may increase the risk of shrinkage.

Ergonomics and Safety

When navigating traditional shelving units, workers may have to climb ladders, bend down, and lift and move heavy goods from place to place, as well as walk great distances per day. Over time, this can contribute to physical strain and ergonomic risks.

Working with a VLM is simpler and safer, as workers can stand comfortably in place, not having to bend, climb, reach, or move unnecessarily.

Cost & ROI

One of the clear benefits of traditional shelving compared to VLMs is that shelving units have far lower up-front costs. They’re relatively cheap to buy and install in a facility, so companies can set up entire aisles of shelves without excessive capital expenditure.

However, even though a VLM requires a larger initial investment, it can provide savings in the long term by improving throughput and productivity. For that reason, companies should assess the total cost of ownership rather than just compare equipment prices alone. Consider elements such as labor, space, productivity, maintenance, and future expansion in the equation.

When Does Traditional Shelving Make More Sense?

The cost-efficient nature of traditional shelving can make it the smarter choice for companies that may not be able to either afford or justify a sizable investment in automation. Since shelving units come in different sizes, they’re also well-suited to facilities that handle irregular, bulky, or palletized inventory, and they’re great for storing slow-moving SKUs, too.

Low-SKU facilities can also benefit from static shelving systems, and they’re efficient additions to warehouses that are very large and well-staffed. It’s important to understand that automation isn’t always necessary, and slow-moving products that may spend several weeks in the warehouse can sit quite comfortably on shelves, rather than taking up space in more expensive automated systems.

When Does a Vertical Lift Module Make More Sense?

A vertical lift module may make more sense for companies that are looking to modernize and streamline their operations, since it can deliver measurable improvements in efficiency and order fulfillment. VLMs are also perfectly tailored for facilities that may have limited amounts of free floor space to work with, but plenty of vertical space in which to expand.

A VLM should also be considered if your facility handles the kinds of items that fit neatly inside standard VLM tray capacity, such as tools and machine parts, and these modules tend to provide the most value in warehouses with high SKU counts and high picking volume. They’re worthwhile if you want to ease the burden on your employees, strengthen security, or cope with a sudden spurt of operational growth.

Can You Combine VLMs and Traditional Shelving?

A warehouse or distribution center can absolutely combine VLMs and traditional shelving. Combining manual storage systems (like shelving) with automated alternatives (like VLMs) is known as a “hybrid storage” strategy and is a popular option among warehouses today. It allows operators to enjoy the best of both worlds: cheaper and simpler traditional shelving can handle products that don’t require automation (like bulky, irregular, or slow-moving goods), while VLMs can be reserved for high-SKU, fast-moving products.

There are several other advantages of employing a hybrid storage system, such as:

• Space Utilization: A hybrid model can help you make the most of both horizontal and vertical space throughout your facility.
• Cost Efficiency: Balancing manual and automated systems means you won’t have to fund a huge initial outlay on advanced storage units.
• Flexibility: Hybrid warehouses tend to be better equipped to cope with the ebbs and flows of supply and demand as seasons and order volumes change.

At the same time, hybrid storage can introduce new challenges. For example, operators may struggle at first to decide which products to store in which systems. Here, the ABC analysis method can help.

In this method, inventory is divided into three categories (A, B, and C) based primarily on annual dollar usage or another key measure. Class A items generally represent the high-value section of inventory and generally receive tighter inventory controls. Class B items have more modest value, while Class C items generally represent the lowest-value portion.

However, ABC shouldn’t be the only determination of whether an item belongs in a VLM or on shelves. Factors such as picking frequency, size, security requirements, and available space are also top considerations.

How to Choose the Right Storage System

To help you choose between traditional shelving and automated storage like VLMs, experts recommend focusing on several key factors related to your warehouse’s size, the kinds of products you handle, and the nature of your operations:

• Space: Think about how much free floor space is available and whether you could extract more value from your warehouse’s vertical space.
• SKUs: Look at the size and weight of the goods your facility handles most often, as well as typical quantities of SKUs in stock at any given time.
• Employees: Think about factors like pick frequency, employee travel time, employee morale, and the risk of fatigue and injuries among your team.
• Labor: Consider the amount you’re spending on labor and whether there are ways to optimize that by adjusting your storage.
• Growth: Look ahead and consider how your operations might grow or change in the months and years ahead so you can prepare for those changes in advance.
• Cost: Think about how much you’re willing to spend on storage upgrades and whether you prefer to spend less now or save money in the future.

Only by evaluating all of these factors will you be able to make the most informed decision that should help your warehouse improve its operations moving forward. Keep in mind that you shouldn’t just invest in automated storage because other warehouses are doing so. It’s important to figure out what works best for your facility, rather than focusing too much on others.

Find the Right Storage Solution for Your Operation

As we’ve explored in this guide, there isn’t necessarily a clear “best” option between automated systems like VLMs and conventional shelving units.

Instead, each system has its own clear advantages, with shelving units being cheaper and simpler to deploy, and VLMs taking up less room, making workers’ lives easier, and helping warehouses become more productive and efficient.

Both are worth considering if you’re looking at options to upgrade your warehouse’s storage. You may find that a hybrid model, incorporating shelving units and VLMs, provides the best overall benefits for your facility.

If you have any doubts, questions, or just want a helping hand to evaluate your options and figure out what works best for you, BoxLogix is ready to assist. Reach out to our friendly team today, and we’ll be happy to help you formulate the most effective automation strategy for your facility.

Frequently Asked Questions (FAQs)

What is the difference between a vertical lift module (VLM) and traditional shelving?

A vertical lift module is an automated storage and retrieval system that stores products vertically and delivers them directly to workers, while traditional shelving requires workers to manually locate and retrieve goods. VLMs can improve space utilization, picking efficiency, and inventory control, while traditional shelving is simpler, less expensive, and well-suited to many types of inventory.

How much space can a vertical lift module save compared to traditional shelving?

The amount of space a vertical lift module can save depends on factors like your facility layout, ceiling height, inventory, and existing storage configuration. Because VLMs store products vertically rather than across long rows of shelving, they can significantly reduce the amount of valuable warehouse floor space dedicated to storage.

What types of inventory are best suited for a vertical lift module?

VLMs are particularly well-suited for high-SKU, frequently picked inventory that can fit efficiently within the module’s trays. This can include tools, medical or industrial parts, machine components, and other relatively small items that benefit from faster picking and tighter inventory control.

What types of inventory should be stored on traditional shelving?

Traditional shelving is often a better fit for bulky, irregular, slow-moving, or lower-SKU inventory that may not benefit enough from automation to justify the investment. It can also be a practical choice for facilities that prioritize flexibility and lower upfront storage costs.

Which is better for your warehouse: VLMs or traditional shelving?

Neither VLMs nor traditional shelving are automatically better for every warehouse, so the right choice depends on your space, inventory, picking volume, labor needs, budget, and future growth. Many facilities may benefit from a hybrid approach that uses VLMs for inventory that benefits most from automation and traditional shelving for products that are simpler or more cost-effective to store manually.